N-CSRS

UNITED STATES
SECURITIES AND EXCHANGE COMMISSION

WASHINGTON, D.C. 20549

FORM N-CSR

CERTIFIED SHAREHOLDER REPORT OF REGISTERED MANAGEMENT
INVESTMENT COMPANIES

Investment Company Act file number 811-10001

Oppenheimer Main Street Opportunity Fund

(Exact name of registrant as specified in charter)

(Exact name of registrant as specified in charter)

6803 South Tucson Way, Centennial, Colorado 80112-3924

(Exact name of registrant as specified in charter)

(Address of principal executive offices) (Zip code)

Robert G. Zack, Esq.
OppenheimerFunds, Inc.
Two World Financial Center, New York, New York 10281-1008

(Exact name of registrant as specified in charter)

(Name and address of agent for service)

Registrant’s telephone number, including area code: (303) 768-3200

Date of fiscal year end: July 31

Date of reporting period: 01/31/2009

Item 1. Reports to Stockholders.

January 31, 2009 Oppenheimer Management Main Street Commentaries and Opportunity Fund^® Semiannual Report MANAGEMENT COMMENTARIES An Interview with Your Fund’s Managers Listing of Top Holdings SEMIANNUAL REPORT Listing of Investments Financial Statements

TOP HOLDINGS AND ALLOCATIONS

Top Ten Common Stock Industries

Oil, Gas & Consumable Fuels	14.8	%
Semiconductors & Semiconductor Equipment	6.1
Software	5.1
Machinery	4.5
Computers & Peripherals	4.3
Energy Equipment & Services	3.9
Insurance	3.9
Specialty Retail	3.5
Communications Equipment	3.2
Aerospace & Defense	3.1

Portfolio holdings and allocations are subject to change. Percentages are as of January 31, 2009, and are based on net assets.

Top Ten Common Stock Holdings

Exxon Mobil Corp.	3.3	%
Chevron Corp.	1.5
International Business Machines Corp.	1.5
Microsoft Corp.	1.4
Hewlett-Packard Co.	1.1
Cisco Systems, Inc.	1.1
Apache Corp.	1.1
ConocoPhillips	1.0
Intel Corp.	1.0
Time Warner, Inc.	1.0

Portfolio holdings and allocations are subject to change. Percentages are as of January 31, 2009, and are based on net assets.

For up-to-date Top 10 Fund holdings, please visit www.oppenheimerfunds.com.

9 | OPPENHEIMER MAIN STREET OPPORTUNITY FUND

TOP HOLDINGS AND ALLOCATIONS

Sector Allocation

Portfolio holdings and allocations are subject to change. Percentages are as of January 31, 2009, and are based on the total market value of common stocks.

10 | OPPENHEIMER MAIN STREET OPPORTUNITY FUND

NOTES

Total returns include changes in share price and reinvestment of dividends and capital gains distributions in a hypothetical investment for the periods shown. Cumulative total returns are not annualized. The Fund’s total returns shown do not reflect the deduction of income taxes on an individual’s investment. Taxes may reduce your actual investment returns on income or gains paid by the Fund or any gains you may realize if you sell your shares.

Investors should consider the Fund’s investment objectives, risks, and other charges and expenses carefully before investing. The Fund’s prospectus contains this and other information about the Fund, and may be obtained by asking your financial advisor, calling us at 1.800.525.7048 or visiting our website at www.oppenheimerfunds.com. Read the prospectus carefully before investing.

The Fund’s investment strategy and focus can change over time. The mention of specific fund holdings does not constitute a recommendation by OppenheimerFunds, Inc.

Class A shares of the Fund were first publicly offered on 9/25/00. Unless otherwise noted, Class A returns include the current maximum initial sales charge of 5.75%.

Class B shares of the Fund were first publicly offered on 9/25/00. Unless otherwise noted, Class B returns include the applicable contingent deferred sales charge of 5% (1-year) and 2% (5-year). Because Class B shares convert to Class A shares 72 months after purchase, the “since inception” return for Class B uses Class A performance for the period after conversion. Class B shares are subject to an annual 0.75% asset-based sales charge.

Class C shares of the Fund were first publicly offered on 9/25/00. Unless otherwise noted, Class C returns include the contingent deferred sales charge of 1% for the 1-year period. Class C shares are subject to an annual 0.75% asset-based sales charge.

Class N shares of the Fund were first publicly offered on 3/1/01. Class N shares are offered only through retirement plans. Unless otherwise noted, Class N returns include the contingent deferred sales charge of 1% for the 1-year period. Class N shares are subject to an annual 0.25% asset-based sales charge.

11 | OPPENHEIMER MAIN STREET OPPORTUNITY FUND

NOTES

Class Y shares of the Fund were first publicly offered on 9/25/00. Class Y shares are offered only to certain institutional investors under a special agreement with the Distributor, and to present or former officers, directors, trustees or employees (and their eligible family members) of the Fund, the Manager, its affiliates, its parent company and the subsidiaries of its parent company, and retirement plans established for the benefit of such individuals.

An explanation of the calculation of performance is in the Fund’s Statement of Additional Information.

12 | OPPENHEIMER MAIN STREET OPPORTUNITY FUND

FUND EXPENSES

Fund Expenses. As a shareholder of the Fund, you incur two types of costs: (1) transaction costs, which may include sales charges (loads) on purchase payments, contingent deferred sales charges on redemptions; and redemption fees (if applicable); and (2) ongoing costs, including management fees; distribution and service fees; and other Fund expenses. These examples are intended to help you understand your ongoing costs (in dollars) of investing in the Fund and to compare these costs with the ongoing costs of investing in other mutual funds.

The examples are based on an investment of $1,000.00 invested at the beginning of the period and held for the entire 6-month period ended January 31, 2009.

Actual Expenses. The first section of the table provides information about actual account values and actual expenses. You may use the information in this section for the class of shares you hold, together with the amount you invested, to estimate the expense that you paid over the period. Simply divide your account value by $1,000.00 (for example, an $8,600.00 account value divided by $1,000.00 = 8.60), then multiply the result by the number in the first section under the heading entitled “Expenses Paid During Period” to estimate the expenses you paid on your account during this period.

Hypothetical Example for Comparison Purposes. The second section of the table provides information about hypothetical account values and hypothetical expenses based on the Fund’s actual expense ratio for each class of shares, and an assumed rate of return of 5% per year for each class before expenses, which is not the actual return. The hypothetical account values and expenses may not be used to estimate the actual ending account balance or expenses you paid for the period. You may use this information to compare the ongoing costs of investing in the Fund and other funds. To do so, compare this 5% hypothetical example for the class of shares you hold with the 5% hypothetical examples that appear in the shareholder reports of the other funds.

Please note that the expenses shown in the table are meant to highlight your ongoing costs only and do not reflect any transactional costs, such as front-end or contingent deferred sales charges (loads), or a $12.00 fee imposed annually on accounts valued at less than $500.00 (subject to exceptions

13 | OPPENHEIMER MAIN STREET OPPORTUNITY FUND

FUND EXPENSES Continued

described in the Statement of Additional Information). Therefore, the “hypothetical” section of the table is useful in comparing ongoing costs only, and will not help you determine the relative total costs of owning different funds. In addition, if these transactional costs were included, your costs would have been higher.

	Beginning		Ending		Expenses
	Account		Account		Paid During
	Value		Value		6 Months Ended
Actual	August 1, 2008		January 31, 2009		January 31, 2009
Class A	$	1,000.00	$	647.30	$	5.08
Class B		1,000.00		643.90		8.34
Class C		1,000.00		644.60		8.17
Class N		1,000.00		645.80		6.21
Class Y		1,000.00		648.20		3.12
Hypothetical
(5% return before expenses)
Class A		1,000.00		1,019.06		6.23
Class B		1,000.00		1,015.12		10.21
Class C		1,000.00		1,015.32		10.01
Class N		1,000.00		1,017.69		7.61
Class Y		1,000.00		1,021.42		3.83

Expenses are equal to the Fund’s annualized expense ratio for that class, multiplied by the average account value over the period, multiplied by 184/365 (to reflect the one-half year period). Those annualized expense ratios, excluding indirect expenses from affiliated fund, based on the 6-month period ended January 31, 2009 are as follows:

Class	Expense Ratios
Class A		1.22	%
Class B		2.00
Class C		1.96
Class N		1.49
Class Y		0.75

The expense ratios reflect reduction to custodian expenses and voluntary waivers or reimbursements of expenses by the Fund’s Manager and Transfer Agent that can be terminated at any time, without advance notice. The “Financial Highlights” tables in the Fund’s financial statements, included in this report, also show the gross expense ratios, without such waivers or reimbursements and reduction to custodian expenses, if applicable.

14 | OPPENHEIMER MAIN STREET OPPORTUNITY FUND

STATEMENT OF INVESTMENTS January 31, 2009 / Unaudited

	Shares		Value
Common Stocks—99.7%
Consumer Discretionary—12.2%
Auto Components—0.7%
American Axle & Manufacturing Holdings, Inc.		95,700	$	104,313
ArvinMeritor, Inc.1		252,800		442,400
Autoliv, Inc.		107,900		1,984,281
BorgWarner, Inc.		68,300		1,152,904
Cooper Tire & Rubber Co.		169,100		789,697
Drew Industries, Inc.2		54,566		470,359
Exide Technologies2		82,600		299,838
Goodyear Tire & Rubber Co. (The)2		157,971		974,681
Johnson Controls, Inc.		72,600		908,226
Lear Corp.2		159,330		144,990
Modine Manufacturing Co.		51,800		141,932
Stoneridge, Inc.2		40,400		79,184
Superior Industries International, Inc.1		27,100		278,317
Tenneco, Inc.2		267,508		492,215
TRW Automotive Holdings Corp.2		229,900		710,391
WABCO Holdings, Inc.		121,300		1,813,435
				10,787,163
Automobiles—0.1%
Thor Industries, Inc.		78,000		825,240
Winnebago Industries, Inc.		77,983		431,246
				1,256,486
Distributors—0.0%
Core-Mark Holding Co., Inc.2		1,700		31,178
Diversified Consumer Services—0.4%
Brink’s Home Security Holdings, Inc.2		18,300		418,521
Career Education Corp.2		87,412		1,905,582
Pre-Paid Legal Services, Inc.1,2		15,900		534,558
Regis Corp.		49,366		555,368
Service Corp. International		109,700		499,135
Steiner Leisure Ltd.2		30,380		757,373
Stewart Enterprises, Inc.1		89,172		304,968
Universal Technical Institute, Inc.2		35,300		618,809
				5,594,314
Hotels, Restaurants & Leisure—1.5%
Ameristar Casinos, Inc.		83,200		746,304
Bally Technologies, Inc.2		54,800		1,106,412
BJ’s Restaurants, Inc.2		22,600		250,860
Bob Evans Farms, Inc.		60,300		1,058,868
Boyd Gaming Corp.1		245,700		1,181,817
Brinker International, Inc.		182,147		1,998,153
California Pizza Kitchen, Inc.2		59,100		612,276
Carnival Corp.		57,610		1,047,926
CEC Entertainment, Inc.2		57,788		1,348,772
Cheesecake Factory, Inc. (The)2		75,555		655,817
Chipotle Mexican Grill, Inc., Cl. B2		905		41,196
Churchill Downs, Inc.		1,400		48,314
CKE Restaurants, Inc.		61,900		513,770
Cracker Barrel Old Country Store, Inc.		48,137		845,767
Denny’s Corp.2		179,700		309,084
DineEquity, Inc.1		51,677		456,825
Domino’s Pizza, Inc.2		6,400		42,816
Dover Downs Gaming & Entertainment, Inc.		2,400		7,656
International Game Technology		42,100		446,260
International Speedway Corp., Cl. A		25,700		598,296
Interval Leisure Group, Inc.2		64,000		320,640

F1 | OPPENHEIMER MAIN STREET OPPORTUNITY FUND

STATEMENT OF INVESTMENTS Unaudited / Continued

	Shares		Value
Hotels, Restaurants & Leisure Continued
Isle of Capri Casinos, Inc.1,2		17,300	$	48,959
Jack in the Box, Inc.2		47,800		1,079,802
Krispy Kreme Doughnuts, Inc.1,2		79,400		110,366
Life Time Fitness, Inc.1,2		41,600		616,096
Marcus Corp. (The)		11,900		122,927
Morgans Hotel Group Co.1,2		17,800		64,970
O’Charley’s, Inc.		3,300		8,250
Orient-Express Hotel Ltd., Cl. A1		29,300		185,176
Panera Bread Co., Cl. A1,2		4,670		219,397
Papa John’s International, Inc.2		8,700		165,387
Peet’s Coffee & Tea, Inc.2		4,000		81,280
Pinnacle Entertainment, Inc.2		109,800		744,444
Red Robin Gourmet Burgers, Inc.2		44,600		543,228
Ruby Tuesday, Inc.2		54,200		67,208
Shuffle Master, Inc.2		51,300		173,907
Sonic Corp.1,2		69,252		674,514
Speedway Motorsports, Inc.		43,000		620,920
Steak n Shake Co. (The)1,2		22,300		127,556
Town Sports International Holdings, Inc.1,2		8,900		17,622
Vail Resorts, Inc.1,2		47,500		1,107,700
WMS Industries, Inc.1,2		77,500		1,722,050
Wyndham Worldwide Corp.		240,550		1,474,572
				23,614,160
Household Durables—1.0%
American Greetings Corp., Cl. A		116,670		506,348
Beazer Homes USA, Inc.2		56,030		57,711
Blyth, Inc.		66,700		227,447
Brookfield Homes Corp.1		13,400		33,366
Cavco Industries, Inc.2		600		14,688
Centex Corp.		162,700		1,384,577
Champion Enterprises, Inc.2		37,600		17,296
CSS Industries, Inc.		9,800		148,666
Ethan Allen Interiors, Inc.		24,600		280,194
Furniture Brands International, Inc.		69,087		141,628
Harman International Industries, Inc.		120,000		1,930,800
Helen of Troy Ltd.2		51,000		533,970
Hovnanian Enterprises, Inc., Cl. A1,2		260,500		440,245
Jarden Corp.2		49,600		517,328
KB Home1		46,976		501,234
La-Z-Boy, Inc.1		134,300		130,271
Lennar Corp., Cl. A		225,500		1,734,095
M/I Homes, Inc.		52,200		461,448
MDC Holdings, Inc.		10,300		315,592
Meritage Homes Corp.2		86,500		953,230
National Presto Industries, Inc.		7,500		503,550
Palm Harbor Homes, Inc.2		15,278		54,084
Ryland Group, Inc. (The)		8,300		129,480
Sealy Corp.2		98,500		182,225
Snap-On, Inc.		43,139		1,301,935
Stanley Works (The)		35,400		1,106,604
Tempur-Pedic International, Inc.		182,800		1,279,600
Whirlpool Corp.		8,600		287,498
				15,175,110

F2 | OPPENHEIMER MAIN STREET OPPORTUNITY FUND

	Shares		Value
Internet & Catalog Retail—0.6%
1-800-FLOWERS.com, Inc.2		66,300	$	166,413
Blue Nile, Inc.1,2		16,750		338,685
Expedia, Inc.2		144,100		1,286,813
HSN, Inc.2		37,800		179,550
Liberty Media Corp.- Interactive, Series A2		237,700		746,378
NetFlix.com, Inc.1,2		52,200		1,886,508
NutriSystem, Inc.1		77,073		993,471
Orbitz Worldwide, Inc.2		48,600		145,800
Overstock.com, Inc.1,2		43,342		475,895
PetMed Express, Inc.1,2		32,400		467,856
Priceline.com, Inc.1,2		28,100		1,885,229
Shutterfly, Inc.2		17,600		116,336
Stamps.com, Inc.2		48,800		399,184
Ticketmaster Entertainment, Inc.2		48,300		287,385
				9,375,503
Leisure Equipment & Products—0.3%
Brunswick Corp.1		303,221		842,954
Callaway Golf Co.		139,400		1,060,834
Eastman Kodak Co.		26,000		117,780
JAKKS Pacific, Inc.2		37,800		693,252
Leapfrog Enterprises, Inc.2		81,700		164,217
Polaris Industries, Inc.1		47,850		1,017,770
Pool Corp.		5,900		93,515
RC2 Corp.2		18,000		104,580
Steinway Musical Instruments, Inc.2		10,152		117,357
				4,212,259
Media—2.7%
Arbitron, Inc.		42,300		635,346
Ascent Media Corp., Cl. A2		10,300		268,624
Belo Corp., Cl. A		178,500		255,255
Cablevision Systems Corp. New York Group, Cl. A		73,400		1,176,602
CBS Corp., Cl. B		777,100		4,445,012
Central European Media Enterprises Ltd., Cl. A2		8,304		81,877
Charter Communications, Inc., Cl. A2		188,200		16,938
Clear Channel Outdoor Holdings, Inc., Cl. A2		89,400		463,092
Cox Radio, Inc., Cl. A1,2		60,500		305,525
Dish Network Corp., Cl. A2		121,600		1,561,344
DreamWorks Animation SKG, Inc., Cl. A2		49,100		1,077,745
Entercom Communications Corp.		19,800		23,166
Entravision Communications Corp.2		17,000		14,280
EW Scripps Co. (The), Cl. A		72,500		116,725
Fisher Communications, Inc.		1,136		17,324
Gannett Co., Inc.1		99,500		574,115
Global Sources Ltd.2		22,770		97,456
Harte-Hanks, Inc.		52,700		332,010
Hearst-Argyle Television, Inc.		4,700		18,518
Journal Communications, Inc.		16,300		29,177
Knology, Inc.2		28,500		133,950
Lamar Advertising Co., Cl. A1,2		131,300		1,183,013
Liberty Media Corp.- Entertainment, Series A2		50,800		932,180
Liberty Media Holding Corp.-Capital, Series A2		3,800		20,862

F3 | OPPENHEIMER MAIN STREET OPPORTUNITY FUND

STATEMENT OF INVESTMENTS Unaudited / Continued

	Shares		Value
Media Continued
Lin TV Corp., Cl. A2		21,709	$	15,196
Live Nation, Inc.2		42,600		222,798
McClatchy Co., Cl. A1		71,500		47,190
McGraw-Hill Cos., Inc. (The)		83,500		1,836,165
Media General, Inc., Cl. A1		33,100		64,545
Mediacom Communications Corp.2		96,700		522,180
Meredith Corp.1		91,800		1,466,046
National CineMedia, Inc.		43,460		438,077
News Corp., Inc., Cl. A		599,750		3,832,403
RCN Corp.2		3,400		12,512
Scholastic Corp.		46,300		504,670
Sinclair Broadcast Group, Inc., Cl. A		45,400		83,990
Time Warner, Inc.		1,592,700		14,859,891
Valassis Communications, Inc.2		10,790		13,811
Viacom, Inc., Cl. B2		52,300		771,425
Walt Disney Co. (The)		168,600		3,486,648
Warner Music Group Corp.1		117,700		241,285
				42,198,968
Multiline Retail—0.4%
Big Lots, Inc.2		155,500		2,091,475
Dillard’s, Inc., Cl. A1		226,000		983,100
Fred’s, Inc.		112,700		1,156,302
Kohl’s Corp.2		18,400		675,464
Nordstrom, Inc.1		71,500		907,335
Retail Ventures, Inc.2		1,700		4,063
				5,817,739
Specialty Retail—3.5%
Abercrombie & Fitch Co., Cl. A		54,340		969,969
Aeropostale, Inc.2		104,500		2,205,995
America’s Car-Mart, Inc.2		13,000		118,170
American Eagle Outfitters, Inc.		182,000		1,639,820
AnnTaylor Stores Corp.2		236,400		1,163,088
Asbury Automotive Group, Inc.		57,700		206,566
AutoNation, Inc.1,2		124,800		1,158,144
Barnes & Noble, Inc.		96,866		1,590,540
bebe stores, inc.		76,000		429,400
Best Buy Co., Inc.1		213,750		5,989,275
Big 5 Sporting Goods Corp.		2,092		11,004
Blockbuster, Inc., Cl. A1,2		280,700		359,296
Borders Group, Inc.2		85,974		37,829
Brown Shoe Co., Inc.		144,200		676,298
Buckle, Inc. (The)		64,900		1,372,635
Cato Corp., Cl. A		52,300		691,929
Charlotte Russe Holding, Inc.2		46,721		240,613
Charming Shoppes, Inc.2		104,287		112,630
Chico’s FAS, Inc.2		348,800		1,381,248
Children’s Place Retail Stores, Inc.2		75,101		1,412,650
Christopher & Banks Corp.		66,475		257,923
Citi Trends, Inc.1,2		54,433		518,746
Coldwater Creek, Inc.2		192,200		542,004
Collective Brands, Inc.2		21,100		225,137
Conn’s, Inc.1,2		15,616		189,891
Dress Barn, Inc. (The)1,2		109,700		945,614
DSW, Inc., Cl. A1,2		32,600		325,348
Finish Line, Inc. (The), Cl. A		139,245		661,414
Foot Locker, Inc.		88,300		649,888
Gap, Inc. (The)		424,080		4,783,622
Genesco, Inc.1,2		43,728		673,411
Group 1 Automotive, Inc.1		82,100		818,537

F4 | OPPENHEIMER MAIN STREET OPPORTUNITY FUND

	Shares		Value
Specialty Retail Continued
Guess?, Inc.		44,400	$	714,396
Gymboree Corp.2		33,900		830,550
Haverty Furniture Cos., Inc.1		60,116		482,130
hhgregg, Inc.2		2,400		19,440
Hibbett Sports, Inc.1,2		32,200		438,242
Hot Topic, Inc.2		113,866		972,416
J. Crew Group, Inc.1,2		34,400		344,000
Jo-Ann Stores, Inc.1,2		72,938		931,418
Limited Brands, Inc.		213,000		1,686,960
Lumber Liquidators, Inc.2		12,774		113,305
Men’s Wearhouse, Inc. (The)1		111,800		1,302,470
Monro Muffler Brake, Inc.		5,700		138,339
New York & Co., Inc.2		68,100		134,838
Office Depot, Inc.2		481,200		1,039,392
OfficeMax, Inc.		108,984		600,502
Pacific Sunwear of California, Inc.2		213,100		266,375
Penske Automotive Group, Inc.1		65,600		486,752
Pep Boys-Manny, Moe & Jack1		116,516		336,731
RadioShack Corp.		107,430		1,231,148
Rent-A-Center, Inc.2		101,824		1,512,086
Ross Stores, Inc.		19,900		585,458
Sally Beauty Holdings, Inc.1,2		121,388		574,165
Sherwin-Williams Co.		11,000		525,250
Signet Jewelers Ltd.		15,400		108,416
Sonic Automotive, Inc.1		101,868		206,792
Stage Stores, Inc.		105,100		751,465
Systemax, Inc.1		41,000		415,330
Talbots, Inc. (The)1		125,880		255,536
Tractor Supply Co.1,2		50,400		1,698,984
Tween Brands, Inc.2		81,910		220,338
Wet Seal, Inc., Cl. A2		123,700		322,857
Williams-Sonoma, Inc.		205,100		1,624,392
Zale Corp.1,2		106,700		132,308
Zumiez, Inc.1,2		51,900		371,085
				53,732,500
Textiles, Apparel & Luxury Goods—1.0%
American Apparel, Inc.1,2		11,500		23,345
Carter’s, Inc.2		18,000		305,820
Coach, Inc.2		74,995		1,094,927
Crocs, Inc.1,2		119,800		143,760
FGX International Holdings Ltd.2		8,616		106,838
Fossil, Inc.2		72,000		830,880
Jones Apparel Group, Inc.		207,516		718,005
K-Swiss, Inc., Cl. A		14,300		153,296
Kenneth Cole Productions, Inc., Cl. A		14,800		94,572
Liz Claiborne, Inc.		379,170		834,174
Maidenform Brands, Inc.2		12,800		114,560
Movado Group, Inc.		11,640		89,395
Oxford Industries, Inc.		52,530		349,850
Perry Ellis International, Inc.2		36,500		140,160
Phillips/Van Heusen Corp.		100,800		1,917,216
Polo Ralph Lauren Corp., Cl. A		23,100		947,793
Quicksilver, Inc.2		412,200		865,620
Skechers USA, Inc., Cl. A2		26,900		267,924
Steven Madden Ltd.2		42,707		742,248
Timberland Co., Cl. A2		124,200		1,364,958
True Religion Apparel, Inc.1,2		26,500		302,365
Unifi, Inc.2		103,000		189,520
UniFirst Corp.		8,400		220,416
Volcom, Inc.2		7,900		65,491
Warnaco Group, Inc. (The)2		86,418		1,956,504

F5 | OPPENHEIMER MAIN STREET OPPORTUNITY FUND

STATEMENT OF INVESTMENTS Unaudited / Continued

	Shares		Value
Textiles, Apparel & Luxury Goods Continued
Wolverine World Wide, Inc.		76,380	$	1,385,533
				15,225,170
Consumer Staples—3.2%
Beverages—0.2%
Coca-Cola Bottling Co. Consolidated		1,314		59,064
Coca-Cola Co. (The)		61,300		2,618,736
PepsiCo, Inc.		19,100		959,393
				3,637,193
Food & Staples Retailing—1.3%
Andersons, Inc. (The)		4,681		76,722
Casey’s General Stores, Inc.		16,700		354,875
CVS Caremark Corp.		81,600		2,193,408
Kroger Co. (The)		45,400		1,021,500
Nash Finch Co.		20,700		890,721
Pantry, Inc. (The)2		59,522		989,851
Safeway, Inc.		417,300		8,942,739
Spartan Stores, Inc.		17,700		328,866
SUPERVALU, Inc.		7,300		128,042
Wal-Mart Stores, Inc.		83,600		3,939,232
Whole Foods Market, Inc.1		27,700		283,925
Winn-Dixie Stores, Inc.2		14,422		198,158
				19,348,039
Food Products—0.2%
B&G Foods, Inc., Cl. A		5,400		25,056
Bunge Ltd.1		5,500		236,170
Darling International, Inc.2		161,500		741,285
Del Monte Foods Co.		73,500		489,510
Diamond Foods, Inc.		24,000		616,320
Fresh Del Monte Produce, Inc.2		5,800		139,780
J&J Snack Foods Corp.		2,000		69,820
Omega Protein Corp.2		37,800		144,396
				2,462,337
Household Products—0.6%
Central Garden & Pet Co., Cl. A2		59,246		355,476
Procter & Gamble Co. (The)		160,067		8,723,652
WD-40 Co.		8,200		205,574
				9,284,702
Personal Products—0.4%
Bare Escentuals, Inc.1,2		107,800		391,314
Chattem, Inc.2		3,500		236,600
Elizabeth Arden, Inc.2		17,600		102,608
Herbalife Ltd.		117,300		2,405,823
Inter Parfums, Inc.		21,240		128,290
NBTY, Inc.2		88,800		1,675,656
Nu Skin Asia Pacific, Inc., Cl. A		25,400		241,046
Prestige Brands Holdings, Inc.2		60,700		385,445
Revlon, Inc., Cl. A2		1,200		7,092
				5,573,874
Tobacco—0.5%
Philip Morris International, Inc.		186,600		6,932,190
Universal Corp.		43,200		1,321,056
				8,253,246
Energy—18.7%
Energy Equipment & Services—3.9%
Allis-Chalmers Energy, Inc.2		69,406		249,862
Baker Hughes, Inc.		104,200		3,471,944
Basic Energy Services, Inc.2		84,528		811,469
BJ Services Co.		89,000		979,000
Bronco Drilling Co., Inc.2		23,000		121,440
Complete Production Services, Inc.2		158,000		1,012,780
Dawson Geophysical Co.2		9,300		148,149

F6 | OPPENHEIMER MAIN STREET OPPORTUNITY FUND

	Shares		Value
Energy Equipment & Services Continued
Diamond Offshore Drilling, Inc.1		12,300	$	771,948
Dresser-Rand Group, Inc.2		99,830		1,944,688
Dril-Quip, Inc.2		20,900		512,050
ENGlobal Corp.2		41,800		129,580
ENSCO International, Inc.		44,300		1,212,048
Exterran Holdings, Inc.1,2		71,600		1,586,656
Global Industries Ltd.2		165,100		569,595
Gulf Island Fabrication, Inc.		40,640		511,658
Gulfmark Offshore, Inc.2		27,500		658,350
Halliburton Co.		176,300		3,041,175
Helix Energy Solutions Group, Inc.2		175,269		902,635
Helmerich & Payne, Inc.		34,000		763,640
Hercules Offshore, Inc.2		145,800		542,376
Hornbeck Offshore Services, Inc.2		26,458		469,365
ION Geophysical Corp.2		43,600		65,400
Key Energy Services, Inc.2		264,400		901,604
Lufkin Industries, Inc.		4,718		164,894
Matrix Service Co.2		56,152		297,044
Nabors Industries Ltd.2		86,500		947,175
NATCO Group, Inc., Cl. A2		10,600		181,578
National Oilwell Varco, Inc.2		98,203		2,596,487
Natural Gas Services Group2		18,100		154,755
Newpark Resources, Inc.2		85,300		359,113
Noble Corp.1		344,000		9,339,600
North American Energy Partners, Inc.2		26,400		54,648
Oceaneering International, Inc.2		77,000		2,653,420
Oil States International, Inc.2		99,000		1,812,690
Parker Drilling Co.2		285,652		605,582
Patterson- UTI Energy, Inc.		128,300		1,226,548
Pioneer Drilling Co.2		35,700		177,429
Precision Drilling Trust		32,443		161,242
Pride International, Inc.2		58,500		943,020
Schlumberger Ltd.		105,600		4,309,536
Seacor Holdings, Inc.2		29,300		1,905,672
Smith International, Inc.		7,200		163,440
Superior Energy Services, Inc.2		68,097		1,060,951
Tetra Technologies, Inc.2		176,400		915,516
Tidewater, Inc.		26,300		1,094,343
Transocean Ltd.2		58,800		3,211,656
Union Drilling, Inc.2		36,900		169,002
Unit Corp.2		61,635		1,537,177
Weatherford International Ltd.2		219,000		2,415,570
Willbros Group, Inc.2		47,388		461,559
				60,297,059
Oil, Gas & Consumable Fuels—14.8%
Abraxas Petroleum Corp.2		39,600		43,164
Alon USA Energy, Inc.1		27,400		323,320
Alpha Natural Resources, Inc.2		28,100		458,592
Anadarko Petroleum Corp.		350,800		12,888,392
Apache Corp.		217,900		16,342,500
Arena Resources, Inc.2		13,300		323,988
ATP Oil & Gas Corp.1,2		117,900		527,013
Berry Petroleum Co., Cl. A		135,049		993,961
Bill Barrett Corp.2		68,400		1,512,324
BPZ Resources, Inc.1,2		4,400		25,344

F7 | OPPENHEIMER MAIN STREET OPPORTUNITY FUND

STATEMENT OF INVESTMENTS Unaudited / Continued

	Shares		Value
Oil, Gas & Consumable Fuels Continued
Brigham Exploration Co.2		51,900	$	129,750
Callon Petroleum Co.2		37,000		78,070
Carrizo Oil & Gas, Inc.1,2		55,300		766,458
Chesapeake Energy Corp.		2,500		39,525
Chevron Corp.		324,271		22,867,591
Cimarex Energy Co.		40,200		998,568
ConocoPhillips		336,175		15,978,398
Contango Oil & Gas Co.2		3,200		142,720
Crosstex Energy, Inc.		10,000		33,200
CVR Energy, Inc.2		101,550		518,921
Delek US Holdings, Inc.		50,040		347,778
Delta Petroleum Corp.1,2		25,300		109,802
Denbury Resources, Inc.2		125,200		1,532,448
Devon Energy Corp.		60,770		3,743,432
DHT Maritime, Inc.		13,736		85,301
Enbridge Energy Management LLC2		2,413		73,662
Encore Acquisition Co.2		48,400		1,315,512
Energy Partners Ltd.2		62,647		72,671
Exxon Mobil Corp.1		665,750		50,916,560
Foundation Coal Holdings, Inc.		112,516		1,825,010
Frontier Oil Corp.		165,700		2,366,196
Frontline Ltd.1		26,200		746,962
Gasco Energy, Inc.2		53,400		22,428
General Maritime Corp.		34,438		365,732
GeoResources, Inc.2		18,800		134,984
Gulfport Energy Corp.2		16,056		61,494
Harvest Natural Resources, Inc.2		13,100		52,400
Hess Corp.		231,408		12,868,599
Holly Corp.		82,500		1,928,025
International Coal Group, Inc.1,2		279,140		675,519
Knightsbridge Tankers Ltd.		24,800		374,480
Marathon Oil Corp.		298,400		8,125,432
Mariner Energy, Inc.2		173,600		1,718,640
Massey Energy Co.		82,800		1,256,904
McMoRan Exploration Co.2		64,200		429,498
Meridian Resource Corp. (The)2		56,700		17,577
Murphy Oil Corp.		144,100		6,366,338
Noble Energy, Inc.		143,000		6,996,990
Occidental Petroleum Corp.		257,500		14,046,625
Overseas Shipholding Group, Inc.		33,400		1,192,380
Patriot Coal Corp.2		75,695		388,315
Penn Virginia Corp.		6,100		125,660
PetroQuest Energy, Inc.2		126,888		803,201
Pioneer Natural Resources Co.		25,800		377,712
Plains Exploration & Production Co.2		75,900		1,603,008
Quicksilver Resources, Inc.1,2		101,800		705,474
Rentech, Inc.2		3,900		2,691
Rosetta Resources, Inc.2		149,300		906,251
SandRidge Energy, Inc.2		105,700		703,962
St. Mary Land & Exploration Co.		26,800		518,580
Stone Energy Corp.2		117,767		1,010,441
Sunoco, Inc.		40,500		1,875,960
Swift Energy Co.2		65,800		1,008,056
Teekay Tankers Ltd., Cl. A		20,900		245,157
Tesoro Corp.		154,300		2,658,589
VAALCO Energy, Inc.2		19,700		147,947
Valero Energy Corp.1		496,500		11,975,580
W&T Offshore, Inc.		109,194		1,372,569

F8 | OPPENHEIMER MAIN STREET OPPORTUNITY FUND

	Shares		Value
Oil, Gas & Consumable Fuels Continued
Walter Industries, Inc.		33,200	$	612,208
Western Refining, Inc.		99,100		1,155,506
Westmoreland Coal Co.2		1,900		17,385
Whiting Petroleum Corp.2		14,200		411,800
Williams (Clayton) Energy, Inc.2		4,100		163,180
XTO Energy, Inc.		71,750		2,661,208
				226,211,618
Financials—9.2%
Capital Markets—1.4%
Affiliated Managers Group, Inc.2		9,900		397,881
Ameriprise Financial, Inc.		55,400		1,116,310
BGC Partners, Inc., Cl. A		22,190		53,478
BlackRock, Inc.		604		65,715
Cohen & Steers, Inc.1		39,300		424,440
E*TRADE Financial Corp.1,2		526,300		599,982
Franklin Resources, Inc.		37,100		1,796,382
GAMCO Investors, Inc., Cl. A1		10,800		337,392
GFI Group, Inc.		25,300		79,442
Goldman Sachs Group, Inc. (The)		36,570		2,952,296
Investment Technology Group, Inc.2		17,800		385,904
Janus Capital Group, Inc.		113,100		593,775
Jefferies Group, Inc.		1,100		12,694
KBW, Inc.2		11,400		214,092
Knight Capital Group, Inc., Cl. A2		101,900		1,837,257
LaBranche & Co., Inc.2		186,104		1,276,673
Lazard Ltd., Cl. A		16,800		445,200
Legg Mason, Inc.		44,700		717,882
Morgan Stanley		17,500		354,025
optionsXpress Holdings, Inc.		13,970		152,133
Penson Worldwide, Inc.2		30,400		181,792
Piper Jaffray Cos., Inc.2		34,100		979,011
Pzena Investment Management, Inc.		9,200		24,288
Sanders Morris Harris Group, Inc.		6,100		25,376
SEI Investments Co.		28,000		354,760
Stifel Financial Corp.2		32,700		1,145,808
SWS Group, Inc.		74,976		1,098,398
T. Rowe Price Group, Inc.1		51,700		1,425,886
TD Ameritrade Holding Corp.2		136,100		1,529,764
thinkorswim Group, Inc.2		17,710		133,179
Thomas Weisel Partners Group, Inc.2		4,665		14,415
Tradestation Group, Inc.2		38,000		209,380
Virtus Investment Partners, Inc.1,2		4,438		26,894
Waddell & Reed Financial, Inc., Cl. A		47,300		667,876
				21,629,780
Commercial Banks—1.6%
1st Source Corp.		6,400		113,920
Amcore Financial, Inc.		4,346		6,041
BancFirst Corp.		2,400		85,488
Boston Private Financial Holdings, Inc.		97,300		458,283
Capital City Bank Group, Inc.		630		10,093
Capitol Bancorp Ltd.1		6,200		37,262
Cascade Bancorp1		15,754		36,864
Cathay Bancorp, Inc.1		41,818		531,089

F9 | OPPENHEIMER MAIN STREET OPPORTUNITY FUND

STATEMENT OF INVESTMENTS Unaudited / Continued

	Shares		Value
Commercial Banks Continued
Central Pacific Financial Corp.1		86,800	$	584,164
Chemical Financial Corp.		10,500		239,400
Citizens Republic Bancorp, Inc.2		26,700		30,705
City Bank Lynnwood, WA1		4,100		12,915
City Holding Co.		20,100		516,771
CoBiz Financial, Inc.1		16,245		77,164
Colonial BancGroup, Inc. (The)1		191,800		151,522
Columbia Banking System, Inc.		16,800		149,520
Community Bank System, Inc.		25,500		457,725
Community Trust Bancorp, Inc.		8,928		249,716
East West Bancorp, Inc.		108,200		1,026,818
First Citizens BancShares, Inc., Cl. A		100		13,986
First Commonwealth Financial Corp.		5,000		47,950
First Community Bancshares, Inc.		2,400		41,304
First Financial Bancorp		4,200		34,104
First Horizon National Corp.1		241,555		2,299,604
First Merchants Corp.		11,050		173,264
First Midwest Bancorp, Inc.		28,900		289,000
Frontier Financial Corp.1		62,100		109,917
Greene Bankshares, Inc.1		13,312		131,656
Guaranty Bancorp2		16,200		24,624
Hancock Holding Co.		3,600		98,532
Hanmi Financial Corp.		13,653		26,077
IBERIABANK Corp.		7,300		309,447
Independent Bank Corp.		2,200		40,788
International Bancshares Corp.		10,800		196,776
MainSource Financial Group, Inc.		19,700		192,469
National Penn Bancshares, Inc.1		61,800		598,224
NBT Bancorp, Inc.		22,400		511,616
Old National Bancorp1		32,600		414,998
Old Second Bancorp, Inc.		800		7,152
Oriental Financial Group, Inc.		32,110		162,156
Pacific Capital Bancorp		89,600		950,656
PacWest Bancorp		56,621		957,461
Park National Corp.1		5,400		292,950
Popular, Inc.1		304,390		834,029
Provident Bankshares Corp.1		116,382		747,172
Regions Financial Corp.		204,300		706,878
Republic Bancorp, Inc., Cl. A1		9,100		163,800
S&T Bancorp, Inc.1		4,000		101,720
Sandy Spring Bancorp, Inc.		9,578		135,241
Santander BanCorp1		17,300		143,936
Simmons First National Corp.		9,600		236,544
South Financial Group, Inc. (The)		150,500		282,940
Southside Bancshares, Inc.		5,800		110,316
Southwest Bancorp, Inc.		3,284		34,416
Sterling Bancorp		29,600		326,192
Sterling Financial Corp., Western US1		52,900		97,865
Susquehanna Bancshares, Inc.1		76,700		843,700

F10 | OPPENHEIMER MAIN STREET OPPORTUNITY FUND

	Shares		Value
Commercial Banks Continued
Tompkins Financial Corp.		8,500	$	426,275
TriCo Bancshares		2,200		44,308
Trustmark Corp.		12,120		246,036
U.S. Bancorp		129,200		1,917,328
UCBH Holdings, Inc.1		187,600		437,108
Umpqua Holdings Corp.1		48,300		473,340
United Community Banks, Inc.1		72,114		371,387
Webster Financial Corp.		76,400		319,352
Wells Fargo & Co.		116,823		2,207,955
WesBanco, Inc.		12,800		264,448
West Coast Bancorp		4,187		12,435
Western Alliance Bancorp1,2		28,544		217,220
Whitney Holding Corp.		6,900		89,631
Wintrust Financial Corp.		36,900		493,353
				24,985,096
Consumer Finance—0.4%
Advance America Cash Advance Centers, Inc.		2,500		3,525
Advanta Corp., Cl. B		4,000		3,120
AmeriCredit Corp.1,2		114,399		538,819
Capital One Financial Corp.		19,500		308,880
Cash America International, Inc.		54,000		987,120
Discover Financial Services1		251,800		1,800,370
Dollar Financial Corp.2		3,100		24,335
EZCORP, Inc., Cl. A2		38,300		519,731
First Cash Financial Services, Inc.2		43,600		733,352
First Marblehead Corp. (The)2		23,476		26,997
Nelnet, Inc., Cl. A		46,400		641,248
Student Loan Corp. (The)		3,700		173,678
World Acceptance Corp.1,2		17,400		333,210
				6,094,385
Diversified Financial Services—1.0%
Asset Acceptance Capital Corp.1,2		8,100		33,939
Bank of America Corp.		489,641		3,221,838
CIT Group, Inc.		366,700		1,023,093
Encore Capital Group, Inc.2		15,900		83,634
Financial Federal Corp.		48,526		1,053,985
Interactive Brokers Group, Inc., Cl. A2		70,698		1,079,558
JPMorgan Chase & Co.		211,452		5,394,141
Life Partners Holdings, Inc.		2,000		76,000
MarketAxess Holdings, Inc.2		16,100		124,292
NewStar Financial, Inc.2		4,500		13,320
NYSE Euronext		78,200		1,720,400
PHH Corp.2		98,900		1,092,845
Pico Holdings, Inc.2		2,400		61,008
				14,978,053
Insurance—3.9%
Allied World Assurance Holdings Ltd.		41,900		1,579,630
Allstate Corp.		20,200		437,734
American Equity Investment Life Holding Co.		86,300		577,347
American Financial Group, Inc.		76,500		1,298,970
American National Insurance Co.		1,000		55,850
American Physicians Capital, Inc.		12,200		518,744

F11 | OPPENHEIMER MAIN STREET OPPORTUNITY FUND

STATEMENT OF INVESTMENTS Unaudited / Continued

	Shares		Value
Insurance Continued
Amerisafe, Inc.2		34,600	$	648,058
AmTrust Financial Services, Inc.		23,200		190,472
Arch Capital Group Ltd.2		8,200		493,230
Aspen Insurance Holdings Ltd.		71,900		1,588,990
Assured Guaranty Ltd.		73,200		558,516
Axis Capital Holdings Ltd.		65,200		1,581,752
Berkley (W.R.) Corp.		67,500		1,787,400
Berkshire Hathaway, Inc., Cl. B2		2,275		6,799,975
Brown & Brown, Inc.		40,900		782,417
Chubb Corp.		48,220		2,053,208
Cincinnati Financial Corp.1		29,400		644,742
Citizens, Inc.1,2		16,608		135,355
CNA Financial Corp.		110,200		1,281,626
CNA Surety Corp.2		27,112		448,704
Conseco, Inc.2		355,800		829,014
Delphi Financial Group, Inc., Cl. A		73,179		1,110,125
EMC Insurance Group, Inc.		1,600		31,072
Employers Holdings, Inc.		74,940		1,014,688
Endurance Specialty Holdings Ltd.1		40,900		1,114,934
FBL Financial Group, Inc., Cl. A		8,858		91,326
First American Corp.		13,330		291,127
First Mercury Financial Corp.2		6,600		72,930
FPIC Insurance Group, Inc.2		14,600		568,378
Genworth Financial, Inc., Cl. A		206,900		480,008
Hanover Insurance Group, Inc.		11,700		472,914
Harleysville Group, Inc.		25,600		728,064
Hartford Financial Services Group, Inc. (The)		37,000		486,920
HCC Insurance Holdings, Inc.		30,500		714,005
Hilltop Holdings, Inc.2		3,100		31,000
Horace Mann Educators Corp.		97,600		912,560
Infinity Property & Casualty Corp.		26,445		1,015,488
IPC Holdings Ltd.		63,700		1,634,542
Lincoln National Corp.		55,000		832,150
Loews Corp.		167,502		4,087,049
Maiden Holdings Ltd.		2,300		10,465
Max Capital Group Ltd.		93,000		1,581,930
Meadowbrook Insurance Group, Inc.		24,144		146,554
Montpelier Re Holdings Ltd.		15,500		219,170
National Interstate Corp.		500		7,940
Navigators Group, Inc. (The)2		3,400		174,556
NYMAGIC, Inc.		284		4,845
Odyssey Re Holdings Corp.		26,946		1,267,809
Old Republic International Corp.		35,828		369,745
OneBeacon Insurance Group Ltd.		31,200		263,640
Partnerre Holdings Ltd.		11,700		766,701
Phoenix Cos., Inc. (The)1		88,771		155,349
Platinum Underwriters Holdings Ltd.		48,400		1,346,004
PMA Capital Corp., Cl. A2		18,310		100,888
Presidential Life Corp.		7,700		74,459

F12 | OPPENHEIMER MAIN STREET OPPORTUNITY FUND

	Shares		Value
Insurance Continued
ProAssurance Corp.2		16,000	$	756,160
Protective Life Corp.		163,800		1,356,264
Prudential Financial, Inc.		91,600		2,358,700
RLI Corp.		14,514		819,896
Safety Insurance Group, Inc.		23,100		808,962
Selective Insurance Group, Inc.		49,300		756,755
StanCorp Financial Group, Inc.		36,300		937,266
State Auto Financial Corp.		11,000		243,100
Stewart Information Services Corp.		10,325		153,223
Transatlantic Holdings, Inc.		21,740		698,941
Travelers Cos., Inc. (The)		18,600		718,704
United America Indemnity Ltd., Cl. A2		9,800		103,684
United Fire & Casualty Co.		14,700		294,735
Unitrin, Inc.		74,800		954,448
UnumProvident Corp.		63,700		901,992
XL Capital Ltd., Cl. A		92,400		267,960
Zenith National Insurance Corp.		26,140		732,966
				59,334,825
Real Estate Investment Trusts—0.4%
Alexandria Real Estate Equities, Inc.		6,600		391,644
Apartment Investment & Management Co.		7,351		65,350
BioMed Realty Trust, Inc.		30,690		338,818
Boston Properties, Inc.		2,800		121,240
BRE Properties, Inc., Cl. A		2,800		71,092
CapitalSource, Inc.		13,800		50,232
Corporate Office Properties Trust		3,130		82,569
Developers Diversified Realty Corp.		9,410		45,168
Digital Realty Trust, Inc.		6,700		213,730
Duke Realty Investments, Inc.		6,900		63,549
Entertainment Properties Trust		2,680		60,702
Equity Residential		5,500		131,615
Essex Property Trust, Inc.		2,200		145,310
Federal Realty Investment Trust		2,900		146,827
HCP, Inc.		6,700		156,378
Health Care REIT, Inc.		4,500		170,145
Highwoods Properties, Inc.		7,500		169,200
Home Properties of New York, Inc.		2,410		86,495
Kimco Realty Corp.		8,600		123,668
Liberty Property Trust		8,100		162,000
Macerich Co. (The)		6,200		91,388
Mack-Cali Realty Corp.		3,900		79,248
National Health Investors, Inc.		3,413		88,909
National Retail Properties, Inc.		19,800		285,714
Nationwide Health Properties, Inc.		6,800		173,604
Omega Healthcare Investors, Inc.		12,290		179,803
Plum Creek Timber Co., Inc.		5,100		156,927
Potlatch Corp.		6,960		175,322
ProLogis		18,200		182,182
Public Storage		2,400		148,488
Regency Centers Corp.		4,800		169,440

F13 | OPPENHEIMER MAIN STREET OPPORTUNITY FUND

STATEMENT OF INVESTMENTS Unaudited / Continued

	Shares		Value
Real Estate Investment Trusts Continued
Senior Housing Properties Trust		13,800	$	223,284
Simon Property Group, Inc.		2,700		116,046
SL Green Realty Corp.		25,700		403,747
Tanger Factory Outlet Centers, Inc.		2,600		78,780
Taubman Centers, Inc.		2,800		55,580
UDR, Inc.		10,900		127,857
Ventas, Inc.		6,000		167,220
Vornado Realty Trust		2,700		137,187
Washington Real Estate Investment Trust		3,400		80,954
Weingarten Realty Investors		4,500		72,855
				5,990,267
Real Estate Management & Development—0.2%
Avatar Holdings, Inc.2		4,400		114,180
CB Richard Ellis Group, Inc., Cl. A2		77,900		280,440
Consolidated- Tomoka Land Co.		400		11,620
Forest City Enterprises, Inc., Cl. A		115,000		777,400
Forestar Group, Inc.2		2,500		27,875
Jones Lang LaSalle, Inc.		57,400		1,355,214
				2,566,729
Thrifts & Mortgage Finance—0.3%
Anchor BanCorp Wisconsin, Inc.1		8,600		17,372
Bank Mutual Corp.		48,800		430,904
BankFinancial Corp.		1,621		15,610
Brookline Bancorp, Inc.		1,400		13,538
Corus Bankshares, Inc.1		5,000		5,550
Danvers Bancorp, Inc.		2,300		28,957
Dime Community Bancshares, Inc.		47,000		472,350
Doral Financial Corp.2		954		4,875
First Place Financial Corp.		13,500		38,745
Flagstar Bancorp, Inc.2		8,100		4,860
Flushing Financial Corp.		28,500		225,720
MGIC Investment Corp.1		437,300		1,206,948
OceanFirst Financial Corp.		10,100		129,482
Ocwen Financial Corp.1,2		69,146		615,399
PMI Group, Inc. (The)		331,900		461,341
Provident Financial Services, Inc.		32,700		357,411
Provident New York Bancorp		17,300		164,350
Radian Group, Inc.		221,100		711,942
Tree.com, Inc.2		6,299		25,007
Trustco Bank Corp. NY		18,800		125,960
				5,056,321
Health Care—7.5%
Biotechnology—0.8%
Allos Therapeutics, Inc.2		14,500		113,535
Amgen, Inc.2		97,300		5,336,905
Array BioPharma, Inc.2		2,800		11,200
Celldex Therapeutics, Inc.2		3,000		22,290
Cubist Pharmaceuticals, Inc.1,2		30,300		648,723
CV Therapeutics, Inc.2		24,100		377,165
Dendreon Corp.2		43,900		147,943
Emergent Biosolutions, Inc.2		29,100		638,163
Enzon Pharmaceuticals, Inc.1,2		70,600		459,606
Facet Biotech Corp.2		38,660		235,053
Geron Corp.1,2		26,930		211,131
GTx, Inc.1,2		13,800		152,352
Human Genome Sciences, Inc.2		166,800		301,908

F14 | OPPENHEIMER MAIN STREET OPPORTUNITY FUND

	Shares		Value
Biotechnology Continued
Incyte Corp.2		71,795	$	210,359
Indevus Pharmaceuticals, Inc.1,2		31,500		167,580
Ligand Pharmaceuticals, Inc., Cl. B2		8,500		18,020
MannKind Corp.1,2		27,136		96,333
Martek Biosciences Corp.1		22,300		589,835
Momenta Pharmaceuticals, Inc.2		32,000		346,560
Nabi Biopharmaceuticals, Inc.2		5,206		21,501
NPS Pharmaceuticals, Inc.2		26,045		162,521
PDL BioPharma, Inc.		193,300		1,240,986
Progenics Pharmaceuticals, Inc.1,2		20,434		148,964
Savient Pharmaceuticals, Inc.2		47,800		264,812
Seattle Genetics, Inc.2		300		3,027
				11,926,472
Health Care Equipment & Supplies—0.8%
Advanced Medical Optics, Inc.2		94,000		2,065,180
Align Technology, Inc.1,2		89,100		702,108
Analogic Corp.		15,500		387,500
AngioDynamics, Inc.2		8,800		119,680
Cardiac Science Corp.2		1,694		9,097
ConMed Corp.2		13,700		214,405
CryoLife, Inc.2		26,900		221,656
Cyberonics, Inc.2		35,400		544,806
Exactech, Inc.2		15,100		192,374
Greatbatch, Inc.2		12,500		291,250
Invacare Corp.		10,800		205,848
Inverness Medical Innovations, Inc.1,2		18,600		455,142
IRIS International, Inc.2		3,700		36,852
Kensey Nash Corp.2		22,500		465,075
Kinetic Concepts, Inc.2		1,300		31,330
Medtronic, Inc.		15,100		505,699
Merit Medical Systems, Inc.2		34,300		527,877
Natus Medical, Inc.2		21,700		167,958
Orthofix International NV2		14,200		226,632
Palomar Medical Technologies, Inc.2		18,600		164,610
Quidel Corp.2		32,700		402,210
Sirona Dental Systems, Inc.2		20,000		240,200
Somanetics Corp.2		31,700		464,088
SonoSite, Inc.2		7,400		140,526
Stereotaxis, Inc.1,2		4,900		12,495
Steris Corp.		9,300		247,380
Symmetry Medical, Inc.2		8,500		58,225
Synovis Life Technologies, Inc.2		11,300		184,077
Varian Medical Systems, Inc.2		4,700		174,511
VNUS Medical Technologies, Inc.2		17,300		276,973
Zimmer Holdings, Inc.2		50,100		1,823,640
Zoll Medical Corp.2		20,400		326,604
				11,886,008
Health Care Providers & Services—3.1%
Aetna, Inc.		337,900		10,474,900
Alliance Imaging, Inc.2		27,300		241,878
Almost Family, Inc.1,2		5,300		163,452
AMERIGROUP Corp.2		67,720		1,894,128
AMN Healthcare Services, Inc.2		32,200		218,960
Assisted Living Concepts, Inc.2		5,900		23,423
Brookdale Senior Living, Inc.1		76,600		520,880

F15 | OPPENHEIMER MAIN STREET OPPORTUNITY FUND

STATEMENT OF INVESTMENTS Unaudited / Continued

	Shares		Value
Health Care Providers & Services Continued
Cardinal Health, Inc.		9,900	$	372,735
Catalyst Health Solutions, Inc.2		35,700		786,114
Centene Corp.2		93,100		1,650,663
Chemed Corp.		22,500		902,925
CIGNA Corp.		95,000		1,649,200
Community Health Systems, Inc.2		22,300		415,672
CorVel Corp.2		6,300		111,132
Coventry Health Care, Inc.2		44,587		674,601
Cross Country Healthcare, Inc.2		18,140		135,869
Enstar Group, Inc. (The)		8,900		146,494
Gentiva Health Services, Inc.2		15,600		394,368
Hanger Orthopedic Group, Inc.2		41,600		567,840
Health Management Associates, Inc., Cl. A2		268,000		426,120
Health Net, Inc.2		170,359		2,492,352
Healthspring, Inc.2		73,260		1,276,189
Healthways, Inc.2		60,400		834,728
InVentiv Health, Inc.2		44,400		423,576
Kindred Healthcare, Inc.2		78,983		1,071,799
Landauer, Inc.		10,400		713,232
LifePoint Hospitals, Inc.2		77,000		1,735,580
Lincare Holdings, Inc.2		28,930		695,767
MedCath Corp.2		17,452		109,773
MEDNAX, Inc.2		16,400		550,548
Molina Healthcare, Inc.2		40,400		708,616
National HealthCare Corp.		500		22,750
Odyssey Healthcare, Inc.2		36,900		366,048
Omnicare, Inc.		8,800		246,048
Owens & Minor, Inc.		5,000		198,850
PharMerica Corp.2		52,200		858,168
RehabCare Group, Inc.2		47,076		656,710
Res-Care, Inc.2		11,200		151,760
Skilled Healthcare Group, Inc., Cl. A2		5,300		44,149
UnitedHealth Group, Inc.		5,900		167,147
Universal American Corp.2		45,300		447,111
Universal Health Services, Inc., Cl. B		7,700		291,445
WellCare Health Plans, Inc.2		64,700		956,266
WellPoint, Inc.2		268,200		11,116,890
				47,906,856
Health Care Technology—0.1%
Allscripts-Misys Healthcare Solutions, Inc.		44,200		372,164
Computer Programs & Systems, Inc.		16,341		410,649
IMS Health, Inc.		13,700		198,924
Omnicell, Inc.2		46,968		366,820
				1,348,557
Life Sciences Tools & Services—0.2%
Albany Molecular Research, Inc.2		29,400		251,958
eResearch Technology, Inc.2		41,000		237,390
Life Sciences Research, Inc.2		6,800		44,880
Life Technologies Corp.2		48,962		1,246,573
Luminex Corp.2		8,700		177,219
Medivation, Inc.2		3,700		69,375
Nektar Therapeutics2		26,092		107,238
Thermo Fisher Scientific, Inc.2		20,100		722,193
Varian, Inc.2		20,700		576,288
				3,433,114

F16 | OPPENHEIMER MAIN STREET OPPORTUNITY FUND

	Shares		Value
Pharmaceuticals—2.5%
Abbott Laboratories		21,700	$	1,203,048
BioMimetic Therapeutics, Inc.2		2,400		19,368
Eli Lilly & Co.		112,850		4,155,137
Endo Pharmaceuticals Holdings, Inc.1,2		77,560		1,742,773
Forest Laboratories, Inc.2		74,570		1,867,233
Johnson & Johnson		249,300		14,382,117
K-V Pharmaceutical Co., Cl. A2		18,100		11,765
King Pharmaceuticals, Inc.2		227,000		1,983,980
Medicis Pharmaceutical Corp., Cl. A		127,300		1,773,289
Noven Pharmaceuticals, Inc.2		42,400		421,032
Pain Therapeutics, Inc.1,2		16,900		112,216
Pfizer, Inc.		598,500		8,726,130
Pozen, Inc.2		10,500		75,390
Questcor Pharmaceuticals, Inc.2		20,600		132,870
Salix Pharmaceuticals Ltd.2		17,690		141,520
Sepracor, Inc.2		23,000		349,600
Vivus, Inc.2		10,600		52,046
Watson Pharmaceuticals, Inc.2		54,300		1,481,304
				38,630,818
Industrials—15.7%
Aerospace & Defense—3.1%
Aerovironment, Inc.1,2		8,500		315,010
American Science & Engineering, Inc.		4,000		312,000
Argon ST, Inc.2		9,100		174,174
Axsys Technologies, Inc.2		9,500		405,650
BE Aerospace, Inc.2		137,000		1,324,790
Boeing Co.		145,424		6,152,889
Ceradyne, Inc.2		66,331		1,513,673
Cubic Corp.		55,095		1,496,380
Ducommun, Inc.		37,600		712,144
DynCorp International, Inc., Cl. A2		3,000		45,120
Esterline Technologies Corp.2		50,900		1,836,981
Gencorp, Inc.2		78,100		226,490
General Dynamics Corp.		81,400		4,617,822
Goodrich Corp.		40,500		1,565,730
Herley Industries, Inc.2		5,548		61,805
Honeywell International, Inc.		60,900		1,998,129
L-3 Communications Holdings, Inc.		40,700		3,216,114
Ladish Co., Inc.2		15,800		179,646
Lockheed Martin Corp.		4,400		360,976
Northrop Grumman Corp.		222,200		10,692,264
Precision Castparts Corp.		38,600		2,507,070
Raytheon Co.		46,910		2,374,584
Stanley, Inc.2		2,900		87,754
Taser International, Inc.2		72,400		367,068
Triumph Group, Inc.		28,800		1,304,064
United Technologies Corp.		85,200		4,088,748
				47,937,075
Air Freight & Logistics—0.1%
Atlas Air Worldwide Holdings, Inc.2		22,400		325,024
Hub Group, Inc., Cl. A2		23,700		537,990
Pacer International, Inc.		90,016		774,138
UTi Worldwide, Inc.		8,200		89,872
				1,727,024

F17 | OPPENHEIMER MAIN STREET OPPORTUNITY FUND

STATEMENT OF INVESTMENTS Unaudited / Continued

	Shares		Value
Airlines—0.4%
AirTran Holdings, Inc.2		233,400	$	956,940
Continental Airlines, Inc., Cl. B1,2		66,100		890,367
Hawaiian Holdings, Inc.2		68,000		276,760
Republic Airways Holdings, Inc.2		73,519		602,121
SkyWest, Inc.		67,400		1,054,810
UAL Corp.1,2		145,505		1,373,567
US Airways Group, Inc.2		232,600		1,318,842
				6,473,407
Building Products—0.7%
Aaon, Inc.		36,400		659,568
American Woodmark Corp.		12,500		188,125
Ameron International Corp.		23,800		1,186,430
Apogee Enterprises, Inc.		49,800		510,450
Armstrong World Industries, Inc.		60,500		1,003,090
Gibraltar Industries, Inc.		78,300		801,009
Griffon Corp.2		95,646		951,678
Insteel Industries, Inc.		73,700		567,490
Lennox International, Inc.		36,900		1,037,259
NCI Building Systems, Inc.1,2		47,590		551,568
Owens Corning, Inc.2		35,517		473,797
Quanex Building Products Corp.		65,694		557,742
Trex Co., Inc.1,2		54,980		813,154
Universal Forest Products, Inc.		42,938		901,698
				10,203,058
Commercial Services & Supplies—2.5%
Acco Brands Corp.2		65,598		125,948
Administaff, Inc.		55,170		1,163,535
Advisory Board Co. (The)2		5,900		103,250
American Ecology Corp.		21,400		426,930
American Reprographics Co.2		69,300		421,344
AMREP Corp.2		3,100		86,025
ATC Technology Corp.2		23,200		302,760
Bowne & Co., Inc.		18,823		52,704
Brink’s Co. (The)		32,800		866,904
Casella Waste Systems, Inc., Cl. A2		16,200		44,712
CBIZ, Inc.1,2		58,000		471,540
CDI Corp.		69,100		740,752
Cenveo, Inc.2		87,700		346,415
Clean Harbors, Inc.2		5,100		272,901
Comfort Systems USA, Inc.		64,300		657,789
Consolidated Graphics, Inc.2		21,900		352,809
Copart, Inc.2		22,100		532,389
Cornell Corrections, Inc.2		16,720		255,147
Corporate Executive Board Co. (The)		48,013		969,863
CoStar Group, Inc.2		30,300		897,486
Courier Corp.		4,500		70,695
CRA International, Inc.2		27,400		575,674
Deluxe Corp.		116,460		1,342,784
EnergySolutions, Inc.		136,110		611,134
Equifax, Inc.		47,400		1,171,728
Exponent, Inc.2		19,200		470,784
First Advantage Corp., Cl. A2		16,000		203,840
G&K Services, Inc., Cl. A		21,800		402,210
Heidrick & Struggles International, Inc.		48,552		737,990
Hill International, Inc.2		38,800		213,400

F18 | OPPENHEIMER MAIN STREET OPPORTUNITY FUND

	Shares		Value
Commercial Services & Supplies Continued
HNI Corp.1		97,300	$	1,285,333
Hudson Highland Group, Inc.2		17,200		42,312
ICF International, Inc.2		6,400		151,872
Interface, Inc., Cl. A		146,600		598,128
Kelly Services, Inc., Cl. A		40,900		370,554
Kforce, Inc.2		32,014		200,088
Kimball International, Inc., Cl. B		4,100		28,249
Knoll, Inc.		62,900		428,978
Korn-Ferry International2		122,500		1,151,500
M&F Worldwide Corp.2		9,276		98,326
Manpower, Inc.		68,300		1,943,818
McGrath Rentcorp		3,600		75,492
Miller (Herman), Inc.		111,600		1,226,484
Mine Safety Appliances Co.1		4,900		96,138
Monster Worldwide, Inc.2		175,500		1,616,355
MPS Group, Inc.2		238,300		1,441,715
On Assignment, Inc.2		47,300		218,999
Pitney Bowes, Inc.		62,400		1,389,024
PRG-Schultz International, Inc.2		900		2,817
R.R. Donnelley & Sons Co.1		145,600		1,421,056
Resources Connection, Inc.2		92,408		1,337,144
Robert Half International, Inc.		102,000		1,728,900
Schawk, Inc.		30,784		250,582
School Specialty, Inc.2		20,400		336,600
Spherion Corp.2		49,600		70,928
Standard Register Co. (The)		51,670		375,641
Steelcase, Inc., Cl. A		203,000		876,960
Sykes Enterprises, Inc.2		23,800		397,698
Team, Inc.2		17,900		353,525
TrueBlue, Inc.2		142,200		1,208,700
United Stationers, Inc.2		30,800		862,708
Viad Corp.		35,900		798,057
Waste Services, Inc.2		17,700		89,739
Watson Wyatt & Co. Holdings		13,800		641,700
				38,007,562
Construction & Engineering—1.2%
Baker (Michael) Corp.2		21,342		746,116
Chicago Bridge & Iron Co. NV		103,400		1,164,284
Dycom Industries, Inc.2		133,600		909,816
EMCOR Group, Inc.2		110,200		2,269,018
Fluor Corp.		97,100		3,777,190
Furmanite Corp.2		2,900		10,788
Granite Construction, Inc.1		34,888		1,228,755
Insituform Technologies, Inc., Cl. A1,2		30,300		568,428
Integrated Electrical Services, Inc.2		12,400		102,548
KBR, Inc.		69,800		988,368
Layne Christensen Co.2		6,600		104,148
MasTec, Inc.2		100,800		1,071,504
Northwest Pipe Co.2		10,300		363,178
Orion Marine Group, Inc.2		1,200		11,880
Perini Corp.2		90,345		1,883,693
Pike Electric Corp.2		49,000		551,250
Shaw Group, Inc. (The)2		82,800		2,301,840
				18,052,804
Electrical Equipment—1.1%
Acuity Brands, Inc.1		67,400		1,811,038
AZZ, Inc.2		20,100		450,240
Baldor Electric Co.1		106,904		1,497,725
Belden, Inc.		95,300		1,244,618

F19 | OPPENHEIMER MAIN STREET OPPORTUNITY FUND

STATEMENT OF INVESTMENTS Unaudited / Continued

	Shares		Value
Electrical Equipment Continued
Brady Corp., Cl. A		2,600	$	54,392
C&D Technologies, Inc.1,2		28,600		85,228
Cooper Industries Ltd., Cl. A		27,700		745,407
Emerson Electric Co.		72,400		2,367,480
Encore Wire Corp.1		58,992		973,958
EnerSys, Inc.2		16,900		153,959
FuelCell Energy, Inc.2		20,900		80,674
GrafTech International Ltd.2		252,740		2,024,447
Hubbell, Inc., Cl. B		27,900		864,900
LSI Industries, Inc.		12,900		58,695
Plug Power, Inc.2		4,700		4,230
Powell Industries, Inc.2		12,000		286,560
Rockwell Automation, Inc.		45,200		1,177,008
Smith (A.O.) Corp.		39,300		1,079,964
Vicor Corp.		14,100		66,552
Woodward Governor Co.		53,500		1,100,495
				16,127,570
Industrial Conglomerates—1.0%
3M Co.		60,900		3,275,811
General Electric Co.		881,800		10,696,234
McDermott International, Inc.2		29,900		310,063
Raven Industries, Inc.		19,700		429,657
Standex International Corp.		20,160		309,456
Tredegar Corp.		54,558		900,207
				15,921,428
Machinery—4.5%
3D Systems Corp.2		800		4,800
Actuant Corp., Cl. A		92,300		1,521,104
AGCO Corp.2		30,800		655,424
Albany International Corp., Cl. A		6,200		62,062
Altra Holdings, Inc.2		26,500		186,295
American Railcar Industries, Inc.		3,100		26,009
Ampco-Pittsburgh Corp.		30,986		572,931
Badger Meter, Inc.1		18,100		426,979
Barnes Group, Inc.		17,000		192,100
Blount International, Inc.2		66,800		559,784
Briggs & Stratton Corp.		58,360		863,144
Bucyrus International, Inc., Cl. A		59,700		925,350
Cascade Corp.		7,600		173,964
Caterpillar, Inc.		167,600		5,170,460
Chart Industries, Inc.2		81,200		686,952
CIRCOR International, Inc.		46,500		1,034,625
Colfax Corp.2		22,385		204,151
Columbus McKinnon Corp.2		47,291		601,542
Commercial Vehicle Group, Inc.2		10,400		10,400
Crane Co.		111,100		1,935,362
Cummins, Inc.		231,500		5,551,370
Deere & Co.		3,700		128,538
Dover Corp.		84,800		2,398,144
Dynamic Materials Corp.		12,715		154,360
EnPro Industries, Inc.2		50,600		925,980
Federal Signal Corp.		114,042		769,784
Flowserve Corp.		5,200		277,212
Gardner Denver, Inc.2		87,900		1,913,583
Gorman-Rupp Co. (The)		21,100		540,160
Graco, Inc.		85,600		1,820,712
Graham Corp.1		11,400		113,544
Greenbrier Cos., Inc.		6,400		35,520
Harsco Corp.		47,100		1,117,212
IDEX Corp.		65,400		1,478,694

F20 | OPPENHEIMER MAIN STREET OPPORTUNITY FUND

	Shares		Value
Machinery Continued
Illinois Tool Works, Inc.		78,900	$	2,576,874
Ingersoll-Rand Co. Ltd., Cl. A		206,810		3,352,390
John Bean Technologies Corp.		27,186		263,704
Joy Global, Inc.		42,500		885,275
K-Tron International, Inc.2		700		50,197
Kadant, Inc.2		19,300		193,772
Kennametal, Inc.		117,500		1,884,700
L.B. Foster Co., Cl. A2		16,600		438,074
Lincoln Electric Holdings, Inc.		39,700		1,634,449
Lydall, Inc.2		28,600		105,534
Manitowoc Co., Inc. (The)		222,996		1,226,478
Met-Pro Corp.		4,700		51,512
Mueller Industries, Inc.		56,200		1,130,744
Mueller Water Products, Inc., Cl. A1		134,400		909,888
NACCO Industries, Inc., Cl. A		6,500		207,935
Navistar International Corp.2		27,700		841,249
NN, Inc.		21,900		37,230
Nordson Corp.1		27,500		830,775
Oshkosh Corp.		192,200		1,387,684
Parker-Hannifin Corp.		214,548		8,197,879
Robbins & Myers, Inc.		71,100		1,229,319
Sauer-Danfoss, Inc.		39,928		301,057
Sun Hydraulics Corp.		22,578		347,701
Tecumseh Products Co., Cl. A2		30,810		252,642
Terex Corp.2		84,900		1,005,216
Thermadyne Holdings Corp.2		8,000		28,000
Timken Co.		136,100		2,026,529
Titan International, Inc.		126,400		980,864
Toro Co. (The)1		64,000		1,895,040
TriMas Corp.2		400		576
Trinity Industries, Inc.1		67,800		780,378
Twin Disc, Inc.		2,600		17,082
Wabash National Corp.		57,036		160,842
Watts Water Technologies, Inc., Cl. A		4,500		100,260
Xerium Technologies, Inc.2		70,400		34,496
				68,404,596
Marine—0.2%
Alexander & Baldwin, Inc.		11,500		253,460
American Commercial Lines, Inc.2		86,500		349,460
Excel Maritime Carriers Ltd.1		7,700		50,820
Genco Shipping & Trading Ltd.1		72,700		1,130,485
Horizon Lines, Inc., Cl. A		15,137		52,071
Kirby Corp.2		21,300		510,774
Star Bulk Carriers Corp.1		59,730		131,406
TBS International Ltd., Cl. A1,2		75,672		744,612
Ultrapetrol Ltd. (Bahamas)2		2,600		5,928
				3,229,016
Road & Rail—0.3%
Amerco2		1,700		52,275
Arkansas Best Corp.		57,100		1,335,569
Avis Budget Group, Inc.2		169,600		117,024
Celadon Group, Inc.2		17,990		140,682
Hertz Global Holdings, Inc.2		54,706		276,812
Marten Transport Ltd.2		45,800		808,828

F21 | OPPENHEIMER MAIN STREET OPPORTUNITY FUND

STATEMENT OF INVESTMENTS Unaudited / Continued

	Shares		Value
Road & Rail Continued
Norfolk Southern Corp.		8,700	$	333,732
Old Dominion Freight Line, Inc.2		2,400		60,192
Werner Enterprises, Inc.1		91,900		1,378,500
YRC Worldwide, Inc.1,2		141,100		406,368
				4,909,982
Trading Companies & Distributors—0.6%
Applied Industrial Technologies, Inc.		67,500		1,065,825
Beacon Roofing Supply, Inc.1,2		48,972		623,414
BlueLinx Holdings, Inc.2		6,400		15,232
DXP Enterprises, Inc.2		13,000		176,540
GATX Corp.		56,274		1,356,203
H&E Equipment Services, Inc.2		30,720		204,902
Houston Wire & Cable Co.		47,200		337,480
Interline Brands, Inc.2		7,344		58,752
MSC Industrial Direct Co., Inc., Cl. A		36,100		1,236,786
RSC Holdings, Inc.1,2		44,200		313,820
Rush Enterprises, Inc., Cl. A2		65,474		595,813
TAL International Group, Inc.		3,400		35,632
Textainer Group Holdings Ltd.		14,768		128,334
United Rentals, Inc.1,2		170,041		948,829
Watsco, Inc.		8,700		287,535
WESCO International, Inc.2		98,375		1,812,068
				9,197,165
Transportation Infrastructure—0.0%
CAI International, Inc.2		26,700		60,075
Information Technology—24.1%
Communications Equipment—3.2%
3Com Corp.2		545,497		1,271,008
Acme Packet, Inc.2		33,460		147,224
ADTRAN, Inc.		57,910		877,337
Avanex Corp.2		8,973		16,869
Avocent Corp.2		100,100		1,436,435
BigBand Networks, Inc.2		33,741		170,392
Black Box Corp.		10,497		229,150
Brocade Communications Systems, Inc.2		627,700		2,391,537
Ciena Corp.1,2		168,800		1,053,312
Cisco Systems, Inc.2		1,115,400		16,697,538
CommScope, Inc.2		132,000		1,903,440
Comtech Telecommunications Corp.2		3,800		147,440
Corning, Inc.		186,700		1,887,537
Digi International, Inc.2		26,625		202,350
EchoStar Holding Corp.2		51,800		780,108
Emulex Corp.2		214,000		1,221,940
Extreme Networks, Inc.2		19,855		35,143
F5 Networks, Inc.2		81,400		1,804,638
Finisar Corp.2		285,800		145,758
Harris Corp.		25,000		1,082,250
Harris Stratex Networks, Inc., Cl. A2		17,600		121,440
Hughes Communications, Inc.2		2,800		33,796
InterDigital, Inc.2		63,900		2,065,887
Ixia2		65,418		348,024
JDS Uniphase Corp.2		463,500		1,682,505
Loral Space & Communications Ltd.2		3,500		46,235
Netgear, Inc.2		36,800		409,216
Oplink Communications, Inc.2		8,441		59,678
ParkerVision, Inc.1,2		24,882		44,539
Plantronics, Inc.		115,010		1,167,352

F22 | OPPENHEIMER MAIN STREET OPPORTUNITY FUND

	Shares		Value
Communications Equipment Continued
Polycom, Inc.2		83,300	$	1,170,365
Powerwave Technologies, Inc.2		267,649		120,442
QUALCOMM, Inc.		119,300		4,121,815
SeaChange International, Inc.2		64,100		379,472
Sonus Networks, Inc.2		65,500		86,460
Starent Networks Corp.1,2		42,700		627,690
Symmetricom, Inc.2		14,100		52,311
Tekelec, Inc.2		71,082		882,838
Tellabs, Inc.2		366,000		1,511,580
UTStarcom, Inc.2		88,398		129,945
ViaSat, Inc.2		9,900		219,384
				48,782,380
Computers & Peripherals—4.3%
3PAR, Inc.2		33,300		282,717
Adaptec, Inc.2		154,300		430,497
Apple, Inc.2		26,000		2,343,380
Avid Technology, Inc.1,2		73,100		731,731
Compellent Technologies, Inc.2		3,900		47,190
Data Domain, Inc.1,2		54,400		708,288
Dell, Inc.2		30,188		286,786
Electronics for Imaging, Inc.2		98,800		878,332
EMC Corp.2		155,000		1,711,200
Hewlett-Packard Co.		491,200		17,069,200
Hutchinson Technology, Inc.2		15,639		49,576
Imation Corp.1		49,900		486,026
Intermec, Inc.2		65,500		813,510
International Business Machines Corp.		242,424		22,218,160
Lexmark International, Inc., Cl. A2		59,600		1,411,328
NCR Corp.2		150,000		1,882,500
NetApp, Inc.2		57,400		851,242
Netezza Corp.2		69,750		423,383
Palm, Inc.1,2		131,356		1,007,501
QLogic Corp.2		187,300		2,120,236
Rackable Systems, Inc.2		24,400		95,892
SanDisk Corp.2		180,500		2,063,115
Seagate Technology		289,000		1,095,310
STEC, Inc.1,2		58,000		259,840
Sun Microsystems, Inc.2		461,100		1,918,176
Synaptics, Inc.1,2		77,800		1,833,746
Teradata Corp.2		63,400		832,442
Western Digital Corp.2		150,200		2,204,936
Xyratex Ltd.2		22,400		38,752
				66,094,992
Electronic Equipment & Instruments—2.2%
Agilent Technologies, Inc.2		131,200		2,372,096
Agilysys, Inc.		5,962		21,284
Amphenol Corp., Cl. A		70,500		1,843,575
Anixter International, Inc.1,2		54,200		1,462,316
Arrow Electronics, Inc.2		115,100		2,194,957
Avnet, Inc.2		110,820		2,196,452
AVX Corp.		54,300		495,216
Benchmark Electronics, Inc.2		142,100		1,668,254
Brightpoint, Inc.2		120,100		562,068
Cogent, Inc.2		59,300		690,252
Cognex Corp.		35,700		466,242
Coherent, Inc.2		39,400		712,746
CTS Corp.		57,640		296,270
Daktronics, Inc.		15,600		134,628
Dolby Laboratories, Inc., Cl. A2		10,084		257,747
DTS, Inc.2		25,200		342,720
Electro Scientific Industries, Inc.2		25,300		159,896
Gerber Scientific, Inc.2		7,800		24,492
Ingram Micro, Inc., Cl. A2		125,600		1,541,112

F23 | OPPENHEIMER MAIN STREET OPPORTUNITY FUND

STATEMENT OF INVESTMENTS Unaudited / Continued

	Shares		Value
Electronic Equipment & Instruments Continued
Insight Enterprises, Inc.2		50,600	$	262,108
Itron, Inc.1,2		11,400		744,420
Jabil Circuit, Inc.		203,800		1,186,116
L-1 Identity Solutions, Inc.2		22,970		166,533
Littlefuse, Inc.2		28,900		442,170
Methode Electronics, Inc.		99,700		460,614
Molex, Inc.		144,900		1,937,313
MTS Systems Corp.		16,600		434,754
Multi-Fineline Electronix, Inc.2		32,100		594,813
National Instruments Corp.		43,200		927,504
Newport Corp.2		54,700		292,645
OSI Systems, Inc.2		13,600		198,968
Park Electrochemical Corp.		32,108		563,495
PC Connection, Inc.2		9,600		46,944
Plexus Corp.2		41,652		602,288
RadiSys Corp.2		900		4,257
Rofin-Sinar Technologies, Inc.2		12,501		211,142
Rogers Corp.2		14,400		352,800
Sanmina-SCI Corp.2		524,800		173,184
ScanSource, Inc.2		11,100		207,792
SYNNEX Corp.2		30,500		468,175
Tech Data Corp.2		41,000		742,510
Technitrol, Inc.		48,800		107,360
Trimble Navigation Ltd.2		75,900		1,124,838
TTM Technologies, Inc.2		59,300		357,579
Tyco Electronics Ltd.		93,100		1,318,296
Universal Display Corp.1,2		7,300		55,699
Vishay Intertechnology, Inc.2		394,690		1,168,282
Zygo Corp.2		1,300		7,436
				32,602,358
Internet Software & Services—1.2%
Akamai Technologies, Inc.2		63,300		853,284
Art Technology Group, Inc.2		37,400		63,954
AsiaInfo Holdings, Inc.2		40,100		350,073
Digital River, Inc.2		75,900		1,880,043
EarthLink, Inc.2		218,874		1,648,121
eBay, Inc.2		122,100		1,467,642
Google, Inc., Cl. A2		1,495		506,102
Interwoven, Inc.2		51,700		815,309
j2 Global Communications, Inc.2		90,100		1,764,158
Knot, Inc. (The)2		20,630		141,934
Limelight Networks, Inc.2		1,600		4,896
LoopNet, Inc.2		51,695		336,018
Marchex, Inc., Cl. B1		39,160		196,192
ModusLink Global Solutions, Inc.2		10,100		23,533
Move, Inc.2		6,200		10,478
National Information Consortium, Inc.		26,300		140,442
Open Text Corp.1,2		46,750		1,637,653
Perficient, Inc.2		13,200		51,612
RealNetworks, Inc.2		19,200		54,144
S1 Corp.2		117,200		781,724
Savvis, Inc.2		8,200		52,316
Sohu.com, Inc.2		26,700		1,055,985
SonicWALL, Inc.2		54,700		192,544
Switch & Data Facilities Co.2		16,100		110,768
United Online, Inc.		25,700		157,284
ValueClick, Inc.2		233,100		1,456,875
VeriSign, Inc.2		64,500		1,245,495
Vignette Corp.2		65,100		453,747
VistaPrint Ltd.2		19,400		444,260
Vocus, Inc.2		16,600		253,316
WebMD Health Corp., Cl. A2		7,500		175,800
				18,325,702

F24 | OPPENHEIMER MAIN STREET OPPORTUNITY FUND 

	Shares		Value
IT Services—1.4%
Acxiom Corp.		174,283	$	1,657,431
Affiliated Computer Services, Inc., Cl. A2		24,000		1,100,640
Broadridge Financial Solutions, Inc.		118,400		1,597,216
Cass Information Systems, Inc.		200		4,768
CIBER, Inc.2		152,509		664,939
Computer Sciences Corp.2		58,310		2,148,140
Convergys Corp.2		273,500		2,059,455
CSG Systems International, Inc.2		92,300		1,338,350
DST Systems, Inc.2		25,400		806,958
Euronet Worldwide, Inc.2		17,000		170,850
Exlservice Holdings, Inc.2		16,100		127,995
Fidelity National Information Services, Inc.		4,016		63,895
Forrester Research, Inc.2		16,300		340,344
Gartner, Inc.1,2		76,600		1,084,656
Global Cash Access, Inc.2		54,400		147,424
Hackett Group, Inc. (The)2		4,400		12,364
Heartland Payment Systems, Inc.		23,200		210,424
Hewitt Associates, Inc.2		40,500		1,149,390
iGate Corp.2		41,200		168,508
infoGROUP, Inc.		26,250		96,863
Integral Systems, Inc.2		34,730		379,599
Mastech Holdings, Inc.2		466		871
Maximus, Inc.		8,200		304,712
Ness Technologies, Inc.2		18,500		73,445
NeuStar, Inc., Cl. A2		74,900		1,020,138
Online Resources & Communications Corp.2		1,200		3,792
Perot Systems Corp., Cl. A2		93,100		1,209,369
RightNow Technologies, Inc.2		49,400		288,496
Sapient Corp.2		202,400		862,224
Syntel, Inc.1		7,400		159,470
TeleTech Holdings, Inc.2		89,400		723,246
Total System Services, Inc.		75,200		952,032
Unisys Corp.2		530,500		397,875
Western Union Co.		18,497		252,669
Wright Express Corp.2		20,600		240,196
				21,818,744
Office Electronics—0.6%
Xerox Corp.		1,173,900		7,794,696
Zebra Technologies Corp., Cl. A2		99,900		1,681,317
				9,476,013
Semiconductors & Semiconductor Equipment—6.1%
Actel Corp.2		38,700		349,074
Advanced Analogic Technologies, Inc.2		2,700		8,127
Advanced Energy Industries, Inc.2		102,284		918,510
Advanced Micro Devices, Inc.2		72,300		158,337
Altera Corp.		113,000		1,737,940
Amkor Technology, Inc.2		435,220		1,009,710
Analog Devices, Inc.		150,850		3,013,983
Applied Materials, Inc.		736,500		6,901,005
Applied Micro Circuits Corp.2		179,698		718,792
Atheros Communications, Inc.2		84,100		1,010,041
Atmel Corp.2		335,550		1,120,737
ATMI, Inc.2		81,538		1,101,578
Broadcom Corp., Cl. A2		135,600		2,149,260

F25 | OPPENHEIMER MAIN STREET OPPORTUNITY FUND 

STATEMENT OF INVESTMENTS Unaudited / Continued

	Shares		Value
Semiconductors & Semiconductor Equipment Continued
Brooks Automation, Inc.2		119,698	$	547,020
Cabot Microelectronics Corp.2		46,000		1,046,960
Cirrus Logic, Inc.2		105,300		296,946
Cohu, Inc.		1,293		12,904
Conexant Systems, Inc.2		10,700		7,062
Cymer, Inc.2		46,900		956,760
Diodes, Inc.2		7,300		47,304
DSP Group, Inc.2		29,400		191,394
Entegris, Inc.2		442,297		614,793
Exar Corp.2		57,434		388,828
Fairchild Semiconductor International, Inc., Cl. A2		310,700		1,413,685
FEI Co.2		2,300		41,860
Integrated Device Technology, Inc.2		320,600		1,840,244
Intel Corp.		1,164,000		15,015,600
International Rectifier Corp.2		110,000		1,498,200
Intersil Corp., Cl. A		189,400		1,763,314
IXYS Corp.		28,600		195,910
KLA-Tencor Corp.		112,700		2,258,508
Kulicke & Soffa Industries, Inc.2		25,100		38,403
Lattice Semiconductor Corp.2		311,200		479,248
LSI Corp.2		601,900		1,914,042
Marvell Technology Group Ltd.2		318,200		2,319,678
Mattson Technology, Inc.2		9,200		9,016
MEMC Electronic Materials, Inc.2		95,740		1,302,064
Micrel, Inc.		156,969		1,192,964
MKS Instruments, Inc.2		111,800		1,570,790
Monolithic Power Systems, Inc.2		26,700		324,405
National Semiconductor Corp.		88,100		893,334
Netlogic Microsystems, Inc.2		20,813		441,444
Novellus Systems, Inc.2		162,100		2,235,359
NVIDIA Corp.2		173,244		1,377,290
OmniVision Technologies, Inc.2		140,722		941,430
ON Semiconductor Corp.2		85,000		354,450
Pericom Semiconductor Corp.2		42,300		260,991
PMC-Sierra, Inc.2		329,009		1,602,274
RF Micro Devices, Inc.2		134,500		145,260
Rudolph Technologies, Inc.2		6,900		19,389
Semtech Corp.2		145,290		1,707,158
Silicon Image, Inc.2		231,585		849,917
Silicon Laboratories, Inc.2		72,844		1,677,597
Silicon Storage Technology, Inc.2		46,882		96,108
Skyworks Solutions, Inc.2		90,660		391,651
Standard Microsystems Corp.2		13,300		184,205
Supertex, Inc.1,2		28,138		638,451
Techwell, Inc.2		3,900		22,035
Teradyne, Inc.2		367,700		1,768,637
Tessera Technologies, Inc.2		32,200		378,672
Texas Instruments, Inc.		920,900		13,767,455
Ultratech, Inc.2		54,600		611,520
Varian Semiconductor Equipment Associates, Inc.2		97,000		1,846,880
Veeco Instruments, Inc.2		76,900		371,427

F26 | OPPENHEIMER MAIN STREET OPPORTUNITY FUND  

	Shares		Value
Semiconductors & Semiconductor Equipment Continued
Verigy Ltd.2		79,600	$	661,476
Volterra Semiconductor Corp.1,2		38,200		267,400
Xilinx, Inc.		88,300		1,487,855
Zoran Corp.2		90,600		538,164
				93,022,825
Software—5.1%
Advent Software, Inc.1,2		21,200		462,796
Amdocs Ltd.2		79,600		1,346,832
Ansys, Inc.2		31,600		785,576
Aspen Technology, Inc.2		49,620		332,454
Autodesk, Inc.2		128,200		2,122,992
Blackbaud, Inc.		34,200		380,646
BMC Software, Inc.2		9,700		245,701
Bottomline Technologies, Inc.2		11,100		74,148
CA, Inc.		71,400		1,284,486
Cadence Design Systems, Inc.2		351,100		1,327,158
Check Point Software Technologies Ltd.2		48,100		1,090,427
Citrix Systems, Inc.2		55,300		1,163,512
Commvault Systems, Inc.2		15,400		204,358
Compuware Corp.2		280,100		1,820,650
Concur Technologies, Inc.1,2		23,600		582,684
DemandTec, Inc.2		5,900		39,530
EPIQ Systems, Inc.2		41,000		726,520
FactSet Research Systems, Inc.1		23,281		926,584
Fair Isaac Corp.		103,600		1,315,720
Henry (Jack) & Associates, Inc.		25,900		461,020
i2 Technologies, Inc.1,2		1,300		8,112
Intuit, Inc.2		69,700		1,578,705
JDA Software Group, Inc.2		81,300		910,560
Kenexa Corp.2		39,850		270,582
Lawson Software, Inc.2		37,500		158,250
Manhattan Associates, Inc.2		56,200		862,108
Mentor Graphics Corp.2		101,524		473,102
MICROS Systems, Inc.2		54,640		786,816
Microsoft Corp.		1,242,546		21,247,537
MicroStrategy, Inc., Cl. A2		21,600		835,920
MSC.Software Corp.2		21,100		122,802
Net 1 UEPS Technologies, Inc.2		110,900		1,489,387
Nuance Communications, Inc.2		98,100		967,266
Oracle Corp.2		345,400		5,813,082
Parametric Technology Corp.2		165,300		1,487,700
Pegasystems, Inc.		9,000		122,130
Phoenix Technologies Ltd.2		2,600		6,708
Progress Software Corp.2		31,300		533,978
Quest Software, Inc.2		113,500		1,415,345
Radiant Systems, Inc.2		6,600		22,836
Smith Micro Software, Inc.2		37,900		200,870
Solera Holdings, Inc.2		8,600		207,174
SPSS, Inc.2		18,300		469,944
Sybase, Inc.2		73,100		1,996,361
Symantec Corp.2		899,200		13,784,736
Symyx Technologies, Inc.2		19,200		92,160
Synchronoss Technologies, Inc.2		27,700		235,727
Synopsys, Inc.2		89,100		1,648,350

F27 | OPPENHEIMER MAIN STREET OPPORTUNITY FUND  

STATEMENT OF INVESTMENTS Unaudited / Continued

	Shares		Value
Software Continued
Take-Two Interactive Software, Inc.		126,500	$	888,030
Taleo Corp., Cl. A2		7,690		64,827
TIBCO Software, Inc.2		374,100		2,001,435
Wind River Systems, Inc.2		132,700		1,057,619
				78,453,953
Materials—5.8%
Chemicals—1.8%
Air Products & Chemicals, Inc.		3,400		171,020
American Vanguard Corp.		3,100		44,051
Ashland, Inc.		144,410		1,158,168
Balchem Corp.		5,400		120,582
Cabot Corp.		11,800		157,648
Calgon Carbon Corp.2		37,400		470,118
Celanese Corp., Series A		67,175		715,414
CF Industries Holdings, Inc.		32,500		1,527,500
Chemtura Corp.		626,590		469,943
Cytec Industries, Inc.		74,100		1,514,604
Dow Chemical Co. (The)		60,200		697,718
E.I. du Pont de Nemours & Co.		19,500		447,720
Eastman Chemical Co.		28,700		744,765
Ferro Corp.		57,600		228,096
Fuller (H.B.) Co.		80,400		1,123,188
GenTek, Inc.2		1,600		21,840
Innophos Holdings, Inc.		20,800		314,704
Innospec, Inc.		36,592		178,203
Koppers Holdings, Inc.		29,200		473,040
Landec Corp.2		4,700		25,850
LSB Industries, Inc.2		24,000		177,120
Minerals Technologies, Inc.		27,100		1,024,651
Mosaic Co. (The)		168,460		6,008,968
Nalco Holding Co.		60,300		591,543
NewMarket Corp.		10,300		324,450
NOVA Chemicals Corp.		107,200		191,888
Olin Corp.		70,744		993,953
PolyOne Corp.2		113,100		231,855
Quaker Chemical Corp.		22,200		253,302
Rockwood Holdings, Inc.2		95,300		715,703
RPM International, Inc.		38,900		478,859
Schulman (A.), Inc.		36,355		550,778
Spartech Corp.		61,700		195,589
Stepan Co.		8,100		297,189
Terra Industries, Inc.		97,810		2,003,149
Valhi, Inc.		3,500		51,975
Valspar Corp. (The)		67,600		1,172,860
Westlake Chemical Corp.1		12,700		173,609
Zep, Inc.		40,074		440,413
Zoltek Cos., Inc.1,2		58,800		416,304
				26,898,330
Construction Materials—0.0%
Headwaters, Inc.1,2		118,430		536,488
Containers & Packaging—0.5%
Myers Industries, Inc.		44,100		276,507
Owens-Illinois, Inc.2		58,900		1,119,100
Packaging Corp. of America		48,400		687,280
Rock-Tenn Co., Cl. A		39,630		1,235,267
Sealed Air Corp.		78,700		1,066,385
Sonoco Products Co.		62,600		1,435,418
Temple-Inland, Inc.1		287,100		1,627,857
				7,447,814
Metals & Mining—3.1%
A. M. Castle & Co.		46,000		389,160
AK Steel Holding Corp.		186,230		1,502,876
Alcoa, Inc.		731,113		5,695,370

F28 | OPPENHEIMER MAIN STREET OPPORTUNITY FUND 

	Shares		Value
Metals & Mining Continued
Allegheny Technologies, Inc.		42,600	$	941,034
Brush Engineered Materials, Inc.2		67,037		841,985
Carpenter Technology Corp.		96,000		1,584,000
Century Aluminum Co.2		113,305		402,233
Cliffs Natural Resources, Inc.		5,700		132,069
Commercial Metals Co.		109,478		1,258,997
Freeport-McMoRan Copper & Gold, Inc., Cl. B		306,000		7,692,840
General Steel Holdings, Inc.1,2		38,100		105,156
Haynes International, Inc.2		36,070		658,999
Kaiser Aluminum Corp.		13,100		325,404
Nucor Corp.		207,200		8,451,688
Olympic Steel, Inc.		29,541		468,816
Reliance Steel & Aluminum Co.		77,900		1,723,927
RTI International Metals, Inc.1,2		82,156		1,093,496
Schnitzer Steel Industries, Inc.1		50,300		1,975,281
Southern Copper Corp.1		705,700		9,837,458
Stillwater Mining Co.1,2		47,600		197,540
Sutor Technology Group Ltd.2		900		1,692
United States Steel Corp.		48,455		1,455,104
Universal Stainless & Alloy Products, Inc.2		2,200		31,900
Worthington Industries, Inc.1		95,100		956,706
				47,723,731
Paper & Forest Products—0.4%
Buckeye Technologies, Inc.2		63,400		185,128
Clearwater Paper Corp.2		1,988		22,484
Deltic Timber Corp.		10,000		395,700
Domtar Corp.2		768,800		1,145,512
Glatfelter		71,600		623,636
International Paper Co.		141,000		1,285,920
Louisiana-Pacific Corp.		124,700		259,376
MeadWestvaco Corp.		43,900		510,996
Mercer International, Inc.2		13,600		17,408
Neenah Paper, Inc.		12,800		86,144
Schweitzer-Mauduit International, Inc.		15,163		324,488
Verso Paper Corp.		4,600		3,082
Wausau Paper Corp.		97,200		924,372
				5,784,246
Telecommunication Services—2.9%
Diversified Telecommunication Services—2.2%
AT&T, Inc.		525,600		12,940,272
Atlantic Tele-Network, Inc.		10,900		234,350
Cbeyond, Inc.2		47,100		741,354
Cincinnati Bell, Inc.2		474,600		659,694
Cogent Communications Group, Inc.1,2		82,300		547,295
Embarq Corp.		82,700		2,954,044
General Communication, Inc., Cl. A2		23,000		151,110
Global Crossing Ltd.2		29,809		183,027
Iowa Telecommunications Services, Inc.		51,296		659,154
NTELOS Holdings Corp.		37,200		805,008
PAETEC Holding Corp.2		14,200		19,170

F29 | OPPENHEIMER MAIN STREET OPPORTUNITY FUND  

STATEMENT OF INVESTMENTS Unaudited / Continued

	Shares			Value
Diversified Telecommunication Services Continued
Premiere Global Services, Inc.2		106,900		$	1,035,861
Qwest Communications International, Inc.1		486,300			1,565,886
Shenandoah Telecommunications Co.		3,160			77,041
tw telecom, Inc.2		247,300			1,891,845
Verizon Communications, Inc.		252,200			7,533,214
Windstream Corp.		153,000			1,328,040
					33,326,365
Wireless Telecommunication Services—0.7%
Centennial Communications Corp.2		233,100			1,906,758
ICO Global Communication Holdings Ltd.2		40,300			23,777
iPCS, Inc.2		33,112			164,236
NII Holdings, Inc.2		56,800			1,101,920
Sprint Nextel Corp.2		1,001,400			2,433,402
Syniverse Holdings, Inc.2		104,265			1,413,833
Telephone & Data Systems, Inc.		49,100			1,498,041
United States Cellular Corp.2		24,800			1,040,360
USA Mobility, Inc.		54,352			574,501
					10,156,828
Utilities—0.4%
Electric Utilities—0.0%
UIL Holdings Corp.1		4,400			116,292
Energy Traders—0.1%
Mirant Corp.2		42,200			724,574
Reliant Energy, Inc.2		135,370			689,033
					1,413,607
Gas Utilities—0.1%
Laclede Group, Inc. (The)		15,200			689,928
Southwest Gas Corp.		700			18,032
WGL Holdings, Inc.		7,400			237,540
					945,500
Multi-Utilities—0.2%
Avista Corp.		42,312			805,620
CH Energy Group, Inc.		18,000			910,440
Integrys Energy Group, Inc.		11,700			488,475
					2,204,535
Water Utilities—0.0%
American States Water Co.		1,500			51,855
Cascal NV		5,300			24,115
SJW Corp.		15,500			416,792
					492,762
Total Common Stocks (Cost $2,203,295,213)					1,523,730,126
Investment Company—0.0%
Capital Southwest Corp. (Cost $23,495)		200			18,332
Total Investments, at Value (excluding Investments Purchased with Cash Collateral from Securities Loaned) (Cost $2,203,318,708)					1,523,748,458
Investments Purchased with Cash Collateral from Securities Loaned—9.3%3
OFI Liquid Assets Fund, LLC, 1.33%4,5 (Cost $142,464,855)		142,464,855			142,464,855
Total Investments, at Value (Cost $2,345,783,563)		109.0	%		1,666,213,313
Liabilities in Excess of Other Assets		(9.0	)		(137,128,325	)
Net Assets		100.0	%	$	1,529,084,988

F30 | OPPENHEIMER MAIN STREET OPPORTUNITY FUND 

Footnotes to Statement of Investments

1. Partial or fully-loaned security. See Note 5 of accompanying Notes.

2. Non-income producing security.

3. The security/securities have been segregated to satisfy the forward commitment to return the cash collateral received in securities lending transactions upon the borrower’s return of the securities loaned. See Note 5 of accompanying Notes.

4. Is or was an affiliate, as defined in the Investment Company Act of 1940, at or during the period ended January 31, 2009, by virtue of the Fund owning at least 5% of the voting securities of the issuer or as a result of the Fund and the issuer having the same investment adviser. Transactions during the period in which the issuer was an affiliate are as follows:

	Shares		Gross		Gross		Shares
	July 31, 2008		Additions		Reductions		January 31, 2009
OFI Liquid Assets Fund, LLC		188,263,600		567,043,849		612,842,594		142,464,855
Oppenheimer Institutional Money Market Fund, Cl. E		5,173,202		215,407,778		220,580,980		—
					Value		Income
OFI Liquid Assets Fund, LLC					$	142,464,855	$	1,783,555	a
Oppenheimer Institutional Money Market Fund, Cl. E						—		84,509
					$	142,464,855	$	1,868,064

a. Net of compensation to the securities lending agent and rebates paid to the borrowing counterparties.

5. Rate shown is the 7-day yield as of January 31, 2009.

Valuation Inputs

Various data inputs are used in determining the value of each of the Fund’s investments as of the reporting period end. These data inputs are categorized in the following hierarchy under applicable financial accounting standards:

1) Level 1—quoted prices in active markets for identical assets or liabilities (including securities actively traded on a securities exchange)

2) Level 2—inputs other than quoted prices that are observable for the asset (such as quoted prices for similar assets and market corroborated inputs such as interest rates, prepayment speeds, credit risks, etc.)

3) Level 3—unobservable inputs (including the Manager’s own judgments about assumptions that market participants would use in pricing the asset).

The market value of the Fund’s investments was determined based on the following inputs as of January 31, 2009:

	Investments in		Other Financial
Valuation Description	Securities		Instruments*
Level 1—Quoted Prices	$	1,666,212,442	$	—
Level 2—Other Significant Observable Inputs		871		—
Level 3—Significant Unobservable Inputs		—		—
Total	$	1,666,213,313	$	—

*Other financial instruments include options written, currency contracts, futures, forwards and swap contracts. Currency contracts and forwards are reported at their unrealized appreciation/depreciation at measurement date, which represents the change in the contract’s value from trade date. Futures are reported at their variation margin at measurement date, which represents the amount due to/from the Fund at that date. Options written and swaps are reported at their market value at measurement date.

See the accompanying Notes for further discussion of the methods used in determining value of the Fund’s investments, and a summary of changes to the valuation techniques, if any, during the reporting period.

See accompanying Notes to Financial Statements.

F31 | OPPENHEIMER MAIN STREET OPPORTUNITY FUND 

STATEMENT OF ASSETS AND LIABILITIES Unaudited

January 31, 2009

Assets
Investments, at value—see accompanying statement of investments:
Unaffiliated companies (cost $2,203,318,708)	$	1,523,748,458
Affiliated companies (cost $142,464,855)		142,464,855
		1,666,213,313
Receivables and other assets:
Investments sold		9,961,206
Interest and dividends		1,313,154
Shares of beneficial interest sold		1,184,587
Other		327,750
Total assets		1,679,000,010
Liabilities
Bank overdraft		800,841
Return of collateral for securities loaned		142,464,855
Payables and other liabilities:
Shares of beneficial interest redeemed		3,624,506
Investments purchased		1,968,137
Transfer and shareholder servicing agent fees		364,981
Shareholder communications		321,938
Distribution and service plan fees		305,872
Trustees’ compensation		8,905
Other		54,987
Total liabilities		149,915,022
Net Assets	$	1,529,084,988
Composition of Net Assets
Par value of shares of beneficial interest	$	203,240
Additional paid-in capital		2,718,870,631
Accumulated net investment loss		(1,845,490	)
Accumulated net realized loss on investments		(508,573,143	)
Net unrealized depreciation on investments		(679,570,250	)
Net Assets	$	1,529,084,988

F32 | OPPENHEIMER MAIN STREET OPPORTUNITY FUND 

Net Asset Value Per Share

Class A Shares:
Net asset value and redemption price per share (based on net assets of $880,096,147 and 115,704,731 shares of beneficial interest outstanding)	$	7.61
Maximum offering price per share (net asset value plus sales charge of 5.75% of offering price)	$	8.07
Class B Shares:
Net asset value, redemption price (excludes applicable contingent deferred sales charge) and offering price per share (based on net assets of $168,279,061 and 23,077,388 shares of beneficial interest outstanding)	$	7.29
Class C Shares:
Net asset value, redemption price (excludes applicable contingent deferred sales charge) and offering price per share (based on net assets of $259,830,179 and 35,443,994 shares of beneficial interest outstanding)	$	7.33
Class N Shares:
Net asset value, redemption price (excludes applicable contingent deferred sales charge) and offering price per share (based on net assets of $79,658,368 and 10,659,325 shares of beneficial interest outstanding)	$	7.47
Class Y Shares:
Net asset value, redemption price and offering price per share (based on net assets of $141,221,233 and 18,354,549 shares of beneficial interest outstanding)	$	7.69

See accompanying Notes to Financial Statements.

F33 | OPPENHEIMER MAIN STREET OPPORTUNITY FUND 

STATEMENT OF OPERATIONS Unaudited

For the Six Months Ended January 31, 2009

Investment Income
Dividends:
Unaffiliated companies (net of foreign withholding taxes of $9,422)	$	22,720,846
Affiliated companies		84,509
Income from investment of securities lending cash collateral, net—affiliated companies		1,783,555
Interest		26,384
Other income		49,855
Total investment income		24,665,149
Expenses
Management fees		6,954,516
Distribution and service plan fees:
Class A		1,564,378
Class B		1,117,710
Class C		1,764,770
Class N		252,123
Transfer and shareholder servicing agent fees:
Class A		2,389,372
Class B		415,439
Class C		524,864
Class N		205,055
Class Y		95,265
Shareholder communications:
Class A		109,699
Class B		47,687
Class C		28,172
Class N		4,414
Class Y		7,919
Custodian fees and expenses		52,864
Trustees’ compensation		36,497
Other		77,351
Total expenses		15,648,095
Less reduction to custodian expenses		(798	)
Less waivers and reimbursements of expenses		(580,971	)
Net expenses		15,066,326
Net Investment Income		9,598,823
Realized and Unrealized Loss
Net realized loss on investments from unaffiliated companies		(214,412,261	)
Net change in unrealized depreciation on investments		(769,433,362	)
Net Decrease in Net Assets Resulting from Operations	$	(974,246,800	)

See accompanying Notes to Financial Statements.

F34 | OPPENHEIMER MAIN STREET OPPORTUNITY FUND  

STATEMENTS OF CHANGES IN NET ASSETS

	Six Months			Year
	Ended			Ended
	January 31, 2009			July 31,
	(Unaudited)			2008
Operations
Net investment income	$	9,598,823		$	20,158,857
Net realized loss		(214,412,261	)		(128,456,810	)
Net change in unrealized appreciation (depreciation)		(769,433,362	)		(433,338,776	)
Net decrease in net assets resulting from operations		(974,246,800	)		(541,636,729	)
Dividends and/or Distributions to Shareholders
Dividends from net investment income:
Class A		(8,285,617	)		(19,963,759	)
Class B		—			—
Class C		—			(928,338	)
Class N		(610,552	)		(861,600	)
Class Y		(2,512,762	)		(4,685,142	)
		(11,408,931	)		(26,438,839	)
Distributions from net realized gain:
Class A		(3,136,402	)		(234,140,201	)
Class B		(621,756	)		(46,049,006	)
Class C		(970,135	)		(64,871,091	)
Class N		(287,615	)		(14,111,801	)
Class Y		(476,362	)		(35,634,158	)
		(5,492,270	)		(394,806,257	)
Beneficial Interest Transactions
Net increase (decrease) in net assets resulting from beneficial interest transactions:
Class A		(400,438,993	)		(139,003,616	)
Class B		(37,570,696	)		(98,042,332	)
Class C		(59,051,317	)		(46,267,505	)
Class N		(3,955,401	)		24,305,896
Class Y		(107,808,923	)		109,343,158
		(608,825,330	)		(149,664,399	)
Net Assets
Total decrease		(1,599,973,331	)		(1,112,546,224	)
Beginning of period		3,129,058,319			4,241,604,543
End of period (including accumulated net investment loss of $1,845,490 and $35,382, respectively)	$	1,529,084,988		$	3,129,058,319

See accompanying Notes to Financial Statements.

F35 | OPPENHEIMER MAIN STREET OPPORTUNITY FUND 

FINANCIAL HIGHLIGHTS

	Six Months
	Ended
	January 31, 2009												Year Ended July 31,
Class A	(Unaudited)			2008			2007			2006			2005			2004
Per Share Operating Data
Net asset value, beginning of period	$	11.90		$	15.35		$	14.04		$	13.58		$	12.69		$	10.70
Income (loss) from investment operations:
Net investment income (loss)		.05	1		.10	1		.12	1		.09	1		.12	1		(.02	)
Net realized and unrealized gain (loss)		(4.24	)		(1.98	)		1.94			.91			1.86			2.01
Total from investment operations		(4.19	)		(1.88	)		2.06			1.00			1.98			1.99
Dividends and/or distributions to shareholders:
Dividends from net investment income		(.07	)		(.12	)		(.09	)		(.07	)		(.08	)		—
Distributions from net realized gain		(.03	)		(1.45	)		(.66	)		(.47	)		(1.01	)		—
Total dividends and/or distributions to shareholders		(.10	)		(1.57	)		(.75	)		(.54	)		(1.09	)		—
Net asset value, end of period	$	7.61		$	11.90		$	15.35		$	14.04		$	13.58		$	12.69
Total Return, at Net Asset Value2		(35.27	)%		(13.62	)%		14.87	%		7.51	%		16.16	%		18.60	%
Ratios/Supplemental Data
Net assets, end of period (in thousands)	$	880,096		$	1,853,930		$	2,566,678		$	2,284,257		$	1,844,002		$	1,213,822
Average net assets (in thousands)	$	1,262,299		$	2,282,800		$	2,691,156		$	2,044,335		$	1,490,786		$	892,462
Ratios to average net assets:3
Net investment income		1.04	%		0.69	%		0.80	%		0.68	%		0.90	%		0.11	%
Total expenses		1.29	%4		1.12	%4		1.06	%4		1.08	%		1.11	%		1.17	%
Expenses after payments, waivers and/or reimbursements and reduction to custodian expenses		1.22	%		1.12	%		1.06	%		1.08	%		1.11	%		1.17	%
Portfolio turnover rate		35	%		146	%		123	%		107	%		107	%		134	%

1. Per share amounts calculated based on the average shares outstanding during the period.

2. Assumes an investment on the business day before the first day of the fiscal period, with all dividends and distributions reinvested in additional shares on the reinvestment date, and redemption at the net asset value calculated on the last business day of the fiscal period. Sales charges are not reflected in the total returns. Total returns are not annualized for periods less than one full year. Returns do not reflect the deduction of taxes that a shareholder would pay on fund distributions or the redemption of fund shares.

3. Annualized for periods less than one full year.

4. Total expenses including indirect expenses from affiliated fund were as follows:

Six Months Ended January 31, 2009	1.29	%
Year Ended July 31, 2008	1.12	%
Year Ended July 31, 2007	1.06	%

See accompanying Notes to Financial Statements.

F36 | OPPENHEIMER MAIN STREET OPPORTUNITY FUND 

	Six Months
	Ended
	January 31, 2009												Year Ended July 31,
Class B	(Unaudited)			2008			2007			2006			2005			2004
Per Share Operating Data
Net asset value, beginning of period	$	11.36		$	14.71		$	13.50		$	13.11		$	12.31		$	10.47
Income (loss) from investment operations:
Net investment income (loss)		.01	1		(.01	)1		—	1,2		(.02	)1		.01	1		(.07	)
Net realized and unrealized gain (loss)		(4.05	)		(1.89	)		1.87			.88			1.80			1.91
Total from investment operations		(4.04	)		(1.90	)		1.87			.86			1.81			1.84
Dividends and/or distributions to shareholders:
Dividends from net investment income		—			—			—			—			—			—
Distributions from net realized gain		(.03	)		(1.45	)		(.66	)		(.47	)		(1.01	)		—
Total dividends and/or distributions to shareholders		(.03	)		(1.45	)		(.66	)		(.47	)		(1.01	)		—
Net asset value, end of period	$	7.29		$	11.36		$	14.71		$	13.50		$	13.11		$	12.31
Total Return, at Net Asset Value3		(35.61	)%		(14.29	)%		14.03	%		6.64	%		15.17	%		17.57	%
Ratios/Supplemental Data
Net assets, end of period (in thousands)	$	168,279		$	307,836		$	510,881		$	479,198		$	434,456		$	366,608
Average net assets (in thousands)	$	222,945		$	418,258		$	525,389		$	455,267		$	403,468		$	321,870
Ratios to average net assets:4
Net investment income (loss)		0.28	%		(0.07	)%		(0.01	)%		(0.15	)%		0.06	%		(0.76	)%
Total expenses		2.06	%5		1.90	%5		1.87	%5		1.91	%		1.95	%		2.01	%
Expenses after payments, waivers and/or reimbursements and reduction to custodian expenses		2.00	%		1.90	%		1.87	%		1.91	%		1.95	%		2.01	%
Portfolio turnover rate		35	%		146	%		123	%		107	%		107	%		134	%

1. Per share amounts calculated based on the average shares outstanding during the period.

2. Less than $0.005 per share.

3. Assumes an investment on the business day before the first day of the fiscal period, with all dividends and distributions reinvested in additional shares on the reinvestment date, and redemption at the net asset value calculated on the last business day of the fiscal period. Sales charges are not reflected in the total returns. Total returns are not annualized for periods less than one full year. Returns do not reflect the deduction of taxes that a shareholder would pay on fund distributions or the redemption of fund shares.

4. Annualized for periods less than one full year.

5. Total expenses including indirect expenses from affiliated fund were as follows:

Six Months Ended January 31, 2009	2.06	%
Year Ended July 31, 2008	1.90	%
Year Ended July 31, 2007	1.87	%

See accompanying Notes to Financial Statements.

F37 | OPPENHEIMER MAIN STREET OPPORTUNITY FUND 

FINANCIAL HIGHLIGHTS Continued

	Six Months
	Ended
	January 31, 2009												Year Ended July 31,
Class C	(Unaudited)			2008			2007			2006			2005			2004
Per Share Operating Data
Net asset value, beginning of period	$	11.41		$	14.78		$	13.56		$	13.16		$	12.34		$	10.48
Income (loss) from investment operations:
Net investment income (loss)		.01	1		—	1,2		.01	1		(.01	)1		.02	1		(.05	)
Net realized and unrealized gain (loss)		(4.06	)		(1.90	)		1.87			.88			1.81			1.91
Total from investment operations		(4.05	)		(1.90	)		1.88			.87			1.83			1.86
Dividends and/or distributions to shareholders:
Dividends from net investment income		—			(.02	)		—			—			—			—
Distributions from net realized gain		(.03	)		(1.45	)		(.66	)		(.47	)		(1.01	)		—
Total dividends and/or distributions to shareholders		(.03	)		(1.47	)		(.66	)		(.47	)		(1.01	)		—
Net asset value, end of period	$	7.33		$	11.41		$	14.78		$	13.56		$	13.16		$	12.34
Total Return, at Net Asset Value3		(35.54	)%		(14.24	)%		14.04	%		6.69	%		15.30	%		17.75	%
Ratios/Supplemental Data
Net assets, end of period (in thousands)	$	259,830		$	479,789		$	680,871		$	539,720		$	448,492		$	348,928
Average net assets (in thousands)	$	349,696		$	604,615		$	641,709		$	489,988		$	404,242		$	289,046
Ratios to average net assets:4 Net investment income (loss)		0.32	%		(0.01	)%		0.05	%		(0.07	)%		0.16	%		(0.63	)%
Total expenses		1.97	%5		1.83	%5		1.80	%5		1.83	%		1.85	%		1.89	%
Expenses after payments, waivers and/or reimbursements and reduction to custodian expenses		1.96	%		1.83	%		1.80	%		1.83	%		1.85	%		1.89	%
Portfolio turnover rate		35	%		146	%		123	%		107	%		107	%		134	%

1. Per share amounts calculated based on the average shares outstanding during the period.

2. Less than $0.005 per share.

3. Assumes an investment on the business day before the first day of the fiscal period, with all dividends and distributions reinvested in additional shares on the reinvestment date, and redemption at the net asset value calculated on the last business day of the fiscal period. Sales charges are not reflected in the total returns. Total returns are not annualized for periods less than one full year. Returns do not reflect the deduction of taxes that a shareholder would pay on fund distributions or the redemption of fund shares.

4. Annualized for periods less than one full year.

5. Total expenses including indirect expenses from affiliated fund were as follows:

Six Months Ended January 31, 2009	1.97	%
Year Ended July 31, 2008	1.83	%
Year Ended July 31, 2007	1.80	%

See accompanying Notes to Financial Statements.

F38 | OPPENHEIMER MAIN STREET OPPORTUNITY FUND 

	Six Months
	Ended
	January 31, 2009												Year Ended July 31,
Class N	(Unaudited)			2008			2007			2006			2005			2004
Per Share Operating Data
Net asset value, beginning of period	$	11.69		$	15.12		$	13.84		$	13.40		$	12.56		$	10.62
Income (loss) from investment operations:
Net investment income (loss)		.04	1		.05	1		.07	1		.04	1		.06	1		(.04	)
Net realized and unrealized gain (loss)		(4.17	)		(1.94	)		1.92			.90			1.84			1.98
Total from investment operations		(4.13	)		(1.89	)		1.99			.94			1.90			1.94
Dividends and/or distributions to shareholders:
Dividends from net investment income		(.06	)		(.09	)		(.05	)		(.03	)		(.05	)		—
Distributions from net realized gain		(.03	)		(1.45	)		(.66	)		(.47	)		(1.01	)		—
Total dividends and/or distributions to shareholders		(.09	)		(1.54	)		(.71	)		(.50	)		(1.06	)		—
Net asset value, end of period	$	7.47		$	11.69		$	15.12		$	13.84		$	13.40		$	12.56
Total Return, at Net Asset Value2		(35.42	)%		(13.91	)%		14.57	%		7.09	%		15.62	%		18.27	%
Ratios/Supplemental Data
Net assets, end of period (in thousands)	$	79,659		$	129,855		$	141,253		$	90,293		$	58,243		$	33,665
Average net assets (in thousands)	$	100,892		$	141,529		$	123,744		$	73,232		$	46,600		$	22,846
Ratios to average net assets:3
Net investment income (loss)		0.78	%		0.38	%		0.45	%		0.30	%		0.46	%		(0.28	)%
Total expenses		1.56	%4		1.43	%4		1.39	%4		1.45	%		1.54	%		1.62	%
Expenses after payments, waivers and/or reimbursements and reduction to custodian expenses		1.49	%		1.43	%		1.39	%		1.45	%		1.53	%		1.54	%
Portfolio turnover rate		35	%		146	%		123	%		107	%		107	%		134	%

1.	Per share amounts calculated based on the average shares outstanding during the period.
2.	Assumes an investment on the business day before the first day of the fiscal period, with all dividends and distributions reinvested in additional shares on the reinvestment date, and redemption at the net asset value calculated on the last business day of the fiscal period. Sales charges are not reflected in the total returns. Total returns are not annualized for periods less than one full year. Returns do not reflect the deduction of taxes that a shareholder would pay on fund distributions or the redemption of fund shares.
3.	Annualized for periods less than one full year.
4.	Total expenses including indirect expenses from affiliated fund were as follows:

Six Months Ended January 31, 2009	1.56	%
Year Ended July 31, 2008	1.43	%
Year Ended July 31, 2007	1.39	%

See accompanying Notes to Financial Statements.

F39 | OPPENHEIMER MAIN STREET OPPORTUNITY FUND

FINANCIAL HIGHLIGHTS Continued

	Six Months
	Ended
	January 31, 2009												Year Ended July 31,
Class Y	(Unaudited)			2008			2007			2006			2005			2004
Per Share Operating Data
Net asset value, beginning of period	$	12.11		$	15.60		$	14.25		$	13.76		$	12.86		$	10.79
Income (loss) from investment operations:
Net investment income		.07	1		.15	1		.18	1		.14	1		.15	1		.05
Net realized and unrealized gain (loss)		(4.32	)		(2.00	)		1.97			.93			1.89			2.02
Total from investment operations		(4.25	)		(1.85	)		2.15			1.07			2.04			2.07
Dividends and/or distributions to shareholders:
Dividends from net investment income		(.14	)		(.19	)		(.14	)		(.11	)		(.13	)		—
Distributions from net realized gain		(.03	)		(1.45	)		(.66	)		(.47	)		(1.01	)		—
Total dividends and/or distributions to shareholders		(.17	)		(1.64	)		(.80	)		(.58	)		(1.14	)		—
Net asset value, end of period	$	7.69		$	12.11		$	15.60		$	14.25		$	13.76		$	12.86
Total Return, at Net Asset Value2		(35.18	)%		(13.26	)%		15.31	%		7.94	%		16.43	%		19.18	%
Ratios/Supplemental Data
Net assets, end of period (in thousands)	$	141,221		$	357,648		$	341,922		$	149,580		$	44,303		$	6,589
Average net assets (in thousands)	$	220,214		$	368,893		$	262,277		$	90,378		$	27,864		$	5,921
Ratios to average net assets:3
Net investment income		1.51	%		1.11	%		1.14	%		1.01	%		1.14	%		0.57	%
Total expenses		0.75	%4,5,6		0.69	%4,5,6		0.68	% 4,5,6		0.72	%5		0.82	%5		0.67	%5
Portfolio turnover rate		35	%		146	%		123	%		107	%		107	%		134	%

1.	Per share amounts calculated based on the average shares outstanding during the period.
2.	Assumes an investment on the business day before the first day of the fiscal period, with all dividends and distributions reinvested in additional shares on the reinvestment date, and redemption at the net asset value calculated on the last business day of the fiscal period. Sales charges are not reflected in the total returns. Total returns are not annualized for periods less than one full year. Returns do not reflect the deduction of taxes that a shareholder would pay on fund distributions or the redemption of fund shares.
3.	Annualized for periods less than one full year.
4.	Total expenses including indirect expenses from affiliated fund were as follows:

Six Months Ended January 31, 2009	0.75	%
Year Ended July 31, 2008	0.69	%
Year Ended July 31, 2007	0.68	%

5.	Reduction to custodian expenses less than 0.005%.
6.	Waiver or reimbursement of indirect management fees less than 0.005%.

See accompanying Notes to Financial Statements.

F40 | OPPENHEIMER MAIN STREET OPPORTUNITY FUND

NOTESTO FINANCIAL STATEMENTS Unaudited

1. Significant Accounting Policies

Oppenheimer Main Street Opportunity Fund (the “Fund”) is registered under the Investment Company Act of 1940, as amended, as an open-end management investment company. The Fund’s investment objective is to seek long-term capital appreciation. The Fund’s investment adviser is OppenheimerFunds, Inc. (the “Manager”).

     The Fund offers Class A, Class B, Class C, Class N and Class Y shares. Class A shares are sold at their offering price, which is normally net asset value plus a front-end sales charge. Class B, Class C and Class N shares are sold without a front-end sales charge but may be subject to a contingent deferred sales charge (“CDSC”). Class N shares are sold only through retirement plans. Retirement plans that offer Class N shares may impose charges on those accounts. Class Y shares are sold to certain institutional investors without either a front-end sales charge or a CDSC, however, the institutional investor may impose charges on those accounts. All classes of shares have identical rights and voting privileges with respect to the Fund in general and exclusive voting rights on matters that affect that class alone. Earnings, net assets and net asset value per share may differ due to each class having its own expenses, such as transfer and shareholder servicing agent fees and shareholder communications, directly attributable to that class. Class A, B, C and N have separate distribution and/or service plans. No such plan has been adopted for Class Y shares. Class B shares will automatically convert to Class A shares 72 months after the date of purchase.

     The following is a summary of significant accounting policies consistently followed by the Fund.

Securities Valuation. The Fund calculates the net asset value of its shares as of the close of the New York Stock Exchange (the “Exchange”), normally 4:00 P.M. Eastern time, on each day the Exchange is open for trading.

     Effective for fiscal periods beginning after November 15, 2007, FASB Statement of Financial Accounting Standards No. 157, Fair Value Measurements, establishes a hierarchy for measuring fair value of assets and liabilities. As required by the standard, each investment asset or liability of the Fund is assigned a level at measurement date based on the significance and source of the inputs to its valuation. Quoted prices in active markets for identical securities are classified as “Level 1”, inputs other than quoted prices for an asset that are observable are classified as “Level 2” and unobservable inputs, including the Manager’s judgment about the assumptions that a market participant would use in pricing an asset or liability are classified as “Level 3”. The inputs used for valuing securities are not necessarily an indication of the risks associated with investing in those securities. A table summarizing the Fund’s investments under these levels of classification is included following the Statement of Investments.

     Securities are valued using quoted market prices, when available, as supplied primarily either by portfolio pricing services approved by the Board of Trustees or dealers. These securities are typically classified within Level 1 or 2; however, they may be designated as Level 3 if the dealer or portfolio pricing service values a security through an internal model with significant unobservable market data inputs.

F41 | OPPENHEIMER MAIN STREET OPPORTUNITY FUND

NOTES TO FINANCIAL STATEMENTS Unaudited / Continued

1. Significant Accounting Policies Continued

     Securities traded on a registered U.S. securities exchange are valued based on the last sale price of the security reported on the principal exchange on which traded, prior to the time when the Fund’s assets are valued. Securities whose principal exchange is NASDAQ^® are valued based on the official closing prices reported by NASDAQ prior to the time when the Fund’s assets are valued. In the absence of a sale, the security is valued at the last sale price on the prior trading day, if it is within the spread of the current day’s closing “bid” and “asked” prices, and if not, at the current day’s closing bid price. A foreign security traded on a foreign exchange is valued based on the last sale price on the principal exchange on which the security is traded, as identified by the portfolio pricing service used by the Manager, prior to the time when the Fund’s assets are valued. In the absence of a sale, the security is valued at the most recent official closing price on the principal exchange on which it is traded.

     Shares of a registered investment company that are not traded on an exchange are valued at that investment company’s net asset value per share.

     Corporate, government and municipal debt instruments having a remaining maturity in excess of sixty days and all mortgage-backed securities, collateralized mortgage obligations and other asset-backed securities are valued at the mean between the “bid” and “asked” prices.

     “Money market-type” debt instruments with remaining maturities of sixty days or less are valued at cost adjusted by the amortization of discount or premium to maturity (amortized cost), which approximates market value. These securities are typically designated as Level 2.

     In the absence of a readily available quoted market price, including for securities whose values have been materially affected by what the Manager identifies as a significant event occurring before the Fund’s assets are valued but after the close of the securities’ respective exchanges, the Manager, acting through its internal valuation committee, in good faith determines the fair valuation of that asset using consistently applied procedures under the supervision of the Board of Trustees (which reviews those fair valuations by the Manager). Those procedures include certain standardized methodologies to fair value securities. Such methodologies include, but are not limited to, pricing securities initially at cost and subsequently adjusting the value based on: changes in company specific fundamentals, changes in an appropriate securities index, or changes in the value of similar securities which may be adjusted for any discounts related to resale restrictions. When possible, such methodologies use observable market inputs such as quoted prices of similar securities, observable interest rates, currency rates and yield curves. The methodologies used for valuing securities are not necessarily an indication of the risks associated with investing in those securities.

     Fair valued securities may be classified as “Level 3” if the valuation primarily reflects the Manager’s own assumptions about the inputs that market participants would use in valuing such securities.

     There have been no significant changes to the fair valuation methodologies during the period.

F42 | OPPENHEIMER MAIN STREET OPPORTUNITY FUND

Foreign Currency Translation. The Fund’s accounting records are maintained in U.S. dollars. The values of securities denominated in foreign currencies and amounts related to the purchase and sale of foreign securities and foreign investment income are translated into U.S. dollars as of the close of the Exchange, normally 4:00 P.M. Eastern time, on each day the Exchange is open for trading. Foreign exchange rates may be valued primarily using a reliable bank, dealer or service authorized by the Board of Trustees.

     Reported net realized gains and losses from foreign currency transactions arise from sales of portfolio securities, sales and maturities of short-term securities, sales of foreign currencies, exchange rate fluctuations between the trade and settlement dates on securities transactions, and the difference between the amounts of dividends, interest, and foreign withholding taxes recorded on the Fund’s books and the U.S. dollar equivalent of the amounts actually received or paid. Net unrealized appreciation and depreciation on the translation of assets and liabilities denominated in foreign currencies arise from changes in the values of assets and liabilities, including investments in securities at fiscal period end, resulting from changes in exchange rates.

     The effect of changes in foreign currency exchange rates on investments is separately identified from the fluctuations arising from changes in market values of securities held and reported with all other foreign currency gains and losses in the Fund’s Statement of Operations.

Investment in Oppenheimer Institutional Money Market Fund. The Fund is permitted to invest daily available cash balances in an affiliated money market fund. The Fund may invest the available cash in Class E shares of Oppenheimer Institutional Money Market Fund (“IMMF”) to seek current income while preserving liquidity. IMMF is a registered open-end management investment company, regulated as a money market fund under the Investment Company Act of 1940, as amended. The Manager is also the investment adviser of IMMF. When applicable the Fund’s investment in IMMF is included in the Statement of Investments. As a shareholder, the Fund is subject to its proportional share of IMMF’s Class E expenses, including its management fee. The Manager will waive fees and/or reimburse Fund expenses in an amount equal to the indirect management fees incurred through the Fund’s investment in IMMF.

Investments in OFI Liquid Assets Fund, LLC. The Fund is permitted to invest cash collateral received in connection with its securities lending activities. Pursuant to the Fund’s Securities Lending Procedures, the Fund may invest cash collateral in, among other investments, an affiliated money market fund. OFI Liquid Assets Fund, LLC (“LAF”) is a limited liability company whose investment objective is to seek current income and stability of principal. The Manager is also the investment adviser of LAF. LAF is not registered under the Investment Company Act of 1940. However, LAF does comply with the investment restrictions applicable to registered money market funds set forth in Rule 2a-7 adopted under the Investment Company Act. The Fund’s investment in LAF is included in the Statement of Investments. As a shareholder, the Fund is subject to its proportional share of LAF’s expenses, including its management fee of 0.08%.

F43 | OPPENHEIMER MAIN STREET OPPORTUNITY FUND

NOTES TO FINANCIAL STATEMENTS Unaudited / Continued

1. Significant Accounting Policies Continued

Allocation of Income, Expenses, Gains and Losses. Income, expenses (other than those attributable to a specific class), gains and losses are allocated on a daily basis to each class of shares based upon the relative proportion of net assets represented by such class. Operating expenses directly attributable to a specific class are charged against the operations of that class.

Federal Taxes. The Fund intends to comply with provisions of the Internal Revenue Code applicable to regulated investment companies and to distribute substantially all of its investment company taxable income, including any net realized gain on investments not offset by capital loss carryforwards, if any, to shareholders. Therefore, no federal income or excise tax provision is required. The Fund files income tax returns in U.S. federal and applicable state jurisdictions. The statute of limitations on the Fund’s tax return filings generally remain open for the three preceding fiscal reporting period ends.

     During the fiscal year ended July 31, 2008, the Fund did not utilize any capital loss carryforward to offset capital gains realized in that fiscal year. As of July 31, 2008, the Fund had available for federal income tax purposes post-October losses of $283,082,979.

     As of January 31, 2009, the Fund had available for federal income tax purposes an estimated capital loss carryforward of $497,495,240 expiring by 2017. This estimated capital loss carryforward represents carryforward as of the end of the last fiscal year, increased for losses deferred under tax accounting rules to the current fiscal year and is increased or decreased by capital losses or gains realized in the first six months of the current fiscal year. During the six months ended January 31, 2009, it is estimated that the Fund will not utilize any capital loss carryforward to offset realized capital gains.

     Net investment income (loss) and net realized gain (loss) may differ for financial statement and tax purposes. The character of dividends and distributions made during the fiscal year from net investment income or net realized gains may differ from their ultimate characterization for federal income tax purposes. Also, due to timing of dividends and distributions, the fiscal year in which amounts are distributed may differ from the fiscal year in which the income or net realized gain was recorded by the Fund.

     The aggregate cost of securities and other investments and the composition of unrealized appreciation and depreciation of securities and other investments for federal income tax purposes as of January 31, 2009 are noted in the following table. The primary difference between book and tax appreciation or depreciation of securities and other investments, if applicable, is attributable to the tax deferral of losses or tax realization of financial statement unrealized gain or loss.

Federal tax cost of securities	$	2,372,776,871
Gross unrealized appreciation	$	80,690,728
Gross unrealized depreciation		(787,254,286	)
Net unrealized depreciation	$	(706,563,558	)

F44 | OPPENHEIMER MAIN STREET OPPORTUNITY FUND

Trustees’ Compensation. The Board of Trustees has adopted a compensation deferral plan for independent trustees that enables trustees to elect to defer receipt of all or a portion of the annual compensation they are entitled to receive from the Fund. For purposes of determining the amount owed to the Trustee under the plan, deferred amounts are treated as though equal dollar amounts had been invested in shares of the Fund or in other Oppenheimer funds selected by the Trustee. The Fund purchases shares of the funds selected for deferral by the Trustee in amounts equal to his or her deemed investment, resulting in a Fund asset equal to the deferred compensation liability. Such assets are included as a component of “Other” within the asset section of the Statement of Assets and Liabilities. Deferral of trustees’ fees under the plan will not affect the net assets of the Fund, and will not materially affect the Fund’s assets, liabilities or net investment income per share. Amounts will be deferred until distributed in accordance to the compensation deferral plan.

Dividends and Distributions to Shareholders. Dividends and distributions to shareholders, which are determined in accordance with income tax regulations and may differ from U.S. generally accepted accounting principles, are recorded on the ex-dividend date. Income and capital gain distributions, if any, are declared and paid annually or at other times as deemed necessary by the Manager.

Investment Income. Dividend income is recorded on the ex-dividend date or upon ex-dividend notification in the case of certain foreign dividends where the ex-dividend date may have passed. Non-cash dividends included in dividend income, if any, are recorded at the fair market value of the securities received. Interest income is recognized on an accrual basis. Discount and premium, which are included in interest income on the Statement of Operations, are amortized or accreted daily.

Custodian Fees. “Custodian fees and expenses” in the Statement of Operations may include interest expense incurred by the Fund on any cash overdrafts of its custodian account during the period. Such cash overdrafts may result from the effects of failed trades in portfolio securities and from cash outflows resulting from unanticipated shareholder redemption activity. The Fund pays interest to its custodian on such cash overdrafts, to the extent they are not offset by positive cash balances maintained by the Fund, at a rate equal to the Federal Funds Rate plus 0.50%. The “Reduction to custodian expenses” line item, if applicable, represents earnings on cash balances maintained by the Fund during the period. Such interest expense and other custodian fees may be paid with these earnings.

Security Transactions. Security transactions are recorded on the trade date. Realized gains and losses on securities sold are determined on the basis of identified cost.

Indemnifications. The Fund’s organizational documents provide current and former trustees and officers with a limited indemnification against liabilities arising in connection with the performance of their duties to the Fund. In the normal course of business, the Fund may also enter into contracts that provide general indemnifications. The Fund’s maximum exposure under these arrangements is unknown as this would be dependent on future

F45 | OPPENHEIMER MAIN STREET OPPORTUNITY FUND

NOTES TO FINANCIAL STATEMENTS Unaudited / Continued

1. Significant Accounting Policies Continued

claims that may be made against the Fund. The risk of material loss from such claims is considered remote.

Other. The preparation of financial statements in conformity with accounting principles generally accepted in the United States of America requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the financial statements and the reported amounts of increases and decreases in net assets from operations during the reporting period. Actual results could differ from those estimates.

2. Shares of Beneficial Interest

The Fund has authorized an unlimited number of $0.001 par value shares of beneficial interest of each class. Transactions in shares of beneficial interest were as follows:

	Six Months Ended January 31, 2009						Year Ended July 31, 2008
	Shares			Amount			Shares			Amount
Class A
Sold		11,881,643		$	113,217,190			38,809,701		$	537,943,927
Dividends and/or distributions reinvested		1,362,024			10,732,836			16,692,730			230,359,672
Redeemed		(53,321,842	)		(524,389,019	)		(66,879,246	)		(907,307,215	)
Net decrease		(40,078,175	)	$	(400,438,993	)		(11,376,815	)	$	(139,003,616	)
Class B
Sold		1,323,930		$	11,533,800			3,204,462		$	42,423,634
Dividends and/or distributions reinvested		79,365			599,956			3,294,572			43,608,090
Redeemed		(5,435,221	)		(49,704,452	)		(14,128,466	)		(184,074,056	)
Net decrease		(4,031,926	)	$	(37,570,696	)		(7,629,432	)	$	(98,042,332	)
Class C
Sold		2,798,430		$	24,253,232			6,627,025		$	88,689,647
Dividends and/or distributions reinvested		117,875			895,858			4,480,045			59,539,797
Redeemed		(9,508,799	)		(84,200,407	)		(15,122,904	)		(194,496,949	)
Net decrease		(6,592,494	)	$	(59,051,317	)		(4,015,834	)	$	(46,267,505	)
Class N
Sold		1,767,534		$	16,122,153			4,123,875		$	54,936,521
Dividends and/or distributions reinvested		106,230			822,220			1,017,314			13,815,129
Redeemed		(2,322,486	)		(20,899,774	)		(3,376,497	)		(44,445,754	)
Net increase (decrease)		(448,722	)	$	(3,955,401	)		1,764,692		$	24,305,896

F46 | OPPENHEIMER MAIN STREET OPPORTUNITY FUND

	Six Months Ended January 31, 2009						Year Ended July 31, 2008
	Shares			Amount			Shares			Amount
Class Y
Sold		2,211,356		$	20,758,679			11,141,011		$	153,375,817
Dividends and/or distributions reinvested		375,203			2,986,615			2,878,274			40,295,835
Redeemed		(13,757,680	)		(131,554,217	)		(6,406,432	)		(84,328,494	)
Net increase (decrease)		(11,171,121	)	$	(107,808,923	)		7,612,853		$	109,343,158

3. Purchases and Sales of Securities

The aggregate cost of purchases and proceeds from sales of securities, other than short-term obligations and investments in Oppenheimer Institutional Money Market Fund and OFI Liquid Assets Fund, LLC, for the six months ended January 31, 2009, were as follows:

	Purchases		Sales
Investment securities	$	794,054,518	$	1,403,316,100

4. Fees and Other Transactions with Affiliates

Management Fees. Under the investment advisory agreement, the Fund pays the Manager a management fee based on the daily net assets of the Fund at an annual rate as shown in the following table:

Fee Schedule
Up to $200 million	0.75	%
Next $200 million	0.72
Next $200 million	0.69
Next $200 million	0.66
Next $4.2 billion	0.60
Over $5 billion	0.58

Transfer Agent Fees. OppenheimerFunds Services (“OFS”), a division of the Manager, acts as the transfer and shareholder servicing agent for the Fund. The Fund pays OFS a per account fee. For the six months ended January 31, 2009, the Fund paid $3,322,443 to OFS for services to the Fund.

     Additionally, Class Y shares are subject to minimum fees of $10,000 annually for assets of $10 million or more. The Class Y shares are subject to the minimum fees in the event that the per account fee does not equal or exceed the applicable minimum fees. OFS may voluntarily waive the minimum fees.

Distribution and Service Plan (12b-1) Fees. Under its General Distributor’s Agreement with the Fund, OppenheimerFunds Distributor, Inc. (the “Distributor”) acts as the Fund’s principal underwriter in the continuous public offering of the Fund’s classes of shares.

Service Plan for Class A Shares. The Fund has adopted a Service Plan (the “Plan”) for Class A shares under Rule 12b-1 of the Investment Company Act of 1940. Under the Plan, the Fund reimburses the Distributor for a portion of its costs incurred for services provided

F47   |   OPPENHEIMER MAIN STREET OPPORTUNITY FUND

NOTES TO FINANCIAL STATEMENTS Unaudited / Continued

4. Fees and Other Transactions with Affiliates Continued

to accounts that hold Class A shares. Reimbursement is made periodically at an annual rate of up to 0.25% of the average annual net assets of Class A shares of the Fund. The Distributor currently uses all of those fees to pay dealers, brokers, banks and other financial institutions periodically for providing personal service and maintenance of accounts of their customers that hold Class A shares. Any unreimbursed expenses the Distributor incurs with respect to Class A shares in any fiscal year cannot be recovered in subsequent periods. Fees incurred by the Fund under the Plan are detailed in the Statement of Operations.

Distribution and Service Plans for Class B, Class C and Class N Shares. The Fund has adopted Distribution and Service Plans (the “Plans”) for Class B, Class C and Class N shares under Rule 12b-1 of the Investment Company Act of 1940 to compensate the Distributor for its services in connection with the distribution of those shares and servicing accounts. Under the Plans, the Fund pays the Distributor an annual asset-based sales charge of 0.75% on Class B and Class C shares and 0.25% on Class N shares. The Distributor also receives a service fee of 0.25% per year under each plan. If either the Class B, Class C or Class N plan is terminated by the Fund or by the shareholders of a class, the Board of Trustees and its independent trustees must determine whether the Distributor shall be entitled to payment from the Fund of all or a portion of the service fee and/or asset-based sales charge in respect to shares sold prior to the effective date of such termination. The Distributor’s aggregate uncompensated expenses under the Plans at December 31, 2008 for Class B, Class C and Class N shares were $1,187,509, $7,059,241 and $2,111,751, respectively. Fees incurred by the Fund under the Plans are detailed in the Statement of Operations.

Sales Charges. Front-end sales charges and contingent deferred sales charges (“CDSC”) do not represent expenses of the Fund. They are deducted from the proceeds of sales of Fund shares prior to investment or from redemption proceeds prior to remittance, as applicable. The sales charges retained by the Distributor from the sale of shares and the CDSC retained by the Distributor on the redemption of shares is shown in the following table for the period indicated.

			Class A		Class B		Class C		Class N
			Contingent		Contingent		Contingent		Contingent
	Class A		Deferred Sales		Deferred Sales		Deferred Sales		Deferred Sales
	Front-End Sales		Charges		Charges		Charges		Charges
Six Months	Charges Retained		Retained by		Retained by		Retained by		Retained by
Ended	by Distributor		Distributor		Distributor		Distributor		Distributor
January 31, 2009	$	247,579	$	5,756	$	238,695	$	23,308	$	2,360

Waivers and Reimbursements of Expenses. OFS has voluntarily agreed to limit transfer and shareholder servicing agent fees for all classes to 0.35% of average annual net assets per class. During the six months ended January 31, 2009, OFS waived $444,408, $69,911, $26,230 and $37,154 for Class A, Class B, Class C and Class N shares, respectively. This undertaking may be amended or withdrawn at any time.

F48   |   OPPENHEIMER MAIN STREET OPPORTUNITY FUND

     The Manager will waive fees and/or reimburse Fund expenses in an amount equal to the indirect management fees incurred through the Fund’s investment in IMMF. During the six months ended January 31, 2009, the Manager waived $3,268 for IMMF management fees.

5. Securities Lending

The Fund lends portfolio securities from time to time in order to earn additional income in the form of fees or interest on securities received as collateral or the investment of any cash received as collateral. The loans are secured by collateral (either securities, letters of credit, or cash) in an amount not less than 100% of the market value of the loaned securities during the period of the loan. The market value of the loaned securities is determined at the close of each business day and any additional required collateral is delivered to the Fund on the next business day. If the borrower defaults on its obligation to return the securities loaned because of insolvency or other reasons, the Fund could experience delays and cost in recovering the securities loaned or in gaining access to the collateral. The Fund continues to receive the economic benefit of interest or dividends paid on the securities loaned in the form of a substitute payment received from the borrower and recognizes the gain or loss in the fair value of the securities loaned that may occur during the term of the loan. The Fund has the right under the lending agreement to recover the securities from the borrower on demand. As of January 31, 2009, the Fund had on loan securities valued at $133,417,003. Collateral of $142,464,855 was received for the loans, all of which was received in cash and subsequently invested in approved instruments.

6. Recent Accounting Pronouncement

In March 2008, the Financial Accounting Standards Board (“FASB”) issued Statement on Financial Accounting Standards (“SFAS”) No. 161, Disclosures about Derivative Instruments and Hedging Activities. This standard requires enhanced disclosures about derivative and hedging activities, including qualitative disclosures about how and why the Fund uses derivative instruments, how these activities are accounted for, and their effect on the Fund’s financial position, financial performance and cash flows. SFAS No. 161 is effective for financial statements issued for fiscal years and interim periods beginning after November 15, 2008. At this time, management is evaluating the implications of SFAS No. 161 and its impact on the Fund’s financial statements and related disclosures.

F49   |   OPPENHEIMER MAIN STREET OPPORTUNITY FUND

THIS PAGE INTENTIONALLY LEFT BLANK.

F50    |   OPPENHEIMER MAIN STREET OPPORTUNITY FUND

BOARD APPROVAL OF THE FUND’S INVESTMENT ADVISORY AGREEMENT Unaudited

Each year, the Board of Trustees (the “Board”), including a majority of the independent Trustees, is required to determine whether to renew the Fund’s investment advisory agreement (the “Agreement”). The Investment Company Act of 1940, as amended, requires that the Board request and evaluate, and that the Manager provide, such information as may be reasonably necessary to evaluate the terms of the Agreement. The Board employs an independent consultant to prepare a report that provides information, including comparative information, the Board requests for that purpose. In addition, the Board receives information throughout the year regarding Fund services, fees, expenses and performance.

     The Manager and the independent consultant provided information to the Board on the following factors: (i) the nature, quality and extent of the Manager’s services, (ii) the investment performance of the Fund and the Manager, (iii) the fees and expenses of the Fund, including comparative expense information, (iv) the profitability of the Manager and its affiliates, including an analysis of the cost of providing services, (v) whether economies of scale are realized as the Fund grows and whether fee levels reflect these economies of scale for Fund investors and (vi) other benefits to the Manager from its relationship with the Fund. The Board was aware that there are alternatives to retaining the Manager.

     Outlined below is a summary of the principal information considered by the Board as well as the Board’s conclusions.

     Nature, Quality and Extent of Services. The Board considered information about the nature, quality and extent of the services provided to the Fund and information regarding the Manager’s key personnel who provide such services. The Manager’s duties include providing the Fund with the services of the portfolio managers and the Manager’s investment team, who provide research, analysis and other advisory services in regard to the Fund’s investments; securities trading services; oversight of third party service providers; monitoring compliance with applicable Fund policies and procedures and adherence to the Fund’s investment restrictions. The Manager is responsible for providing certain administrative services to the Fund as well. Those services include providing and supervising all administrative and clerical personnel who are necessary in order to provide effective corporate administration for the Fund; compiling and maintaining records with respect to the Fund’s operations; preparing and filing reports required by the Securities and Exchange Commission; preparing periodic reports regarding the operations of the Fund for its shareholders; preparing proxy materials for shareholder meetings; and preparing the registration statements required by Federal and state securities laws for the sale of the Fund’s shares. The Manager also provides the Fund with office space, facilities and equipment.

     The Board also considered the quality of the services provided and the quality of the Manager’s resources that are available to the Fund. The Board took account of the fact that

15   |   OPPENHEIMER MAIN STREET OPPORTUNITY FUND

BOARD APPROVAL OF THE FUND’S INVESTMENT ADVISORY AGREEMENT Unaudited / Continued

the Manager has had over forty years of experience as an investment adviser and that its assets under management rank it among the top mutual fund managers in the United States. The Board evaluated the Manager’s advisory, administrative, accounting, legal and compliance services, and information the Board has received regarding the experience and professional qualifications of the Manager’s key personnel and the size and functions of its staff. In its evaluation of the quality of the portfolio management services provided, the Board considered the experience of Mark Zavanelli and Marc Reinganum, the portfolio managers for the Fund, and the Manager’s investment team and analysts. The Board members also considered the totality of their experiences with the Manager as Directors or Trustees of the Fund and other funds advised by the Manager. The Board considered information regarding the quality of services provided by affiliates of the Manager, which its members have become knowledgeable about in connection with the renewal of the Fund’s service agreements. The Board concluded that in light of the Manager’s experience, reputation, personnel, operations and resources, the Fund benefits from the services provided under the Agreement.

     Investment Performance of the Manager and the Fund. Throughout the year, the Manager provided information on the investment performance of the Fund and the Manager, including comparative performance information. The Board also reviewed information, prepared by the Manager and by the independent consultant, comparing the Fund’s historical performance to relevant market indices and to the performance of other retail front-end load and no-load multi-cap core funds advised by other investment advisers. The Board considered that the Fund outperformed its performance universe median during the five-year period, though it underperformed its performance universe median during the one- and three-year periods. The Board considered the Manager’s assertion that poor stock selection and overweighting in the financials and technology sectors contributed to the Fund’s underperformance in 2007. The Board also considered that year-to-date through May 31, 2008, the Fund was in the third quintile.

     Costs of Services by the Manager. The Board reviewed the fees paid to the Manager and the other expenses borne by the Fund. The Board also considered the comparability of the fees charged and the services provided to the Fund to the fees and services for other clients or accounts advised by the Manager. The independent consultant provided comparative data in regard to the fees and expenses of the Fund and multi-cap core funds with comparable asset levels and distribution features. The Board considered that the Fund’s actual management fees and total expenses were lower than its expense group median.

     Economies of Scale and Profits Realized by the Manager. The Board considered information regarding the Manager’s costs in serving as the Fund’s investment adviser,

16   |   OPPENHEIMER MAIN STREET OPPORTUNITY FUND

including the costs associated with the personnel and systems necessary to manage the Fund, and information regarding the Manager’s profitability from its relationship with the Fund. The Board reviewed whether the Manager may realize economies of scale in managing and supporting the Fund. The Board noted that the Fund currently has management fee breakpoints, which are intended to share with Fund shareholders economies of scale that may exist as the Fund’s assets grow.

     Other Benefits to the Manager. In addition to considering the profits realized by the Manager, the Board considered information that was provided regarding the direct and indirect benefits the Manager receives as a result of its relationship with the Fund, including compensation paid to the Manager’s affiliates. The Board also considered that the Manager must be able to pay and retain experienced professional personnel at competitive rates to provide quality services to the Fund and that maintaining the financial viability of the Manager is important in order for the Manager to continue to provide significant services to the Fund and its shareholders.

     Conclusions. These factors were also considered by the independent Trustees meeting separately from the full Board, assisted by experienced counsel to the Fund and to the independent Trustees. Fund counsel and the independent Trustees’ counsel are independent of the Manager within the meaning and intent of the Securities and Exchange Commission Rules.

     Based on its review of the information it received and its evaluations described above, the Board, including a majority of the independent Trustees, decided to continue the Agreement for another year. In arriving at this decision, the Board did not single out any factor or factors as being more important than others, but considered all of the above information, and considered the terms and conditions of the Agreement, including the management fee, in light of all of the surrounding circumstances.

17   |   OPPENHEIMER MAIN STREET OPPORTUNITY FUND

PORTFOLIO PROXY VOTING POLICIES AND PROCEDURES; UPDATES TO STATEMENTS OF INVESTMENTS Unaudited

The Fund has adopted Portfolio Proxy Voting Policies and Procedures under which the Fund votes proxies relating to securities (“portfolio proxies”) held by the Fund. A description of the Fund’s Portfolio Proxy Voting Policies and Procedures is available (i) without charge, upon request, by calling the Fund toll-free at 1.800.525.7048, (ii) on the Fund’s website at www.oppenheimerfunds.com, and (iii) on the SEC’s website at www.sec.gov. In addition, the Fund is required to file Form N-PX, with its complete proxy voting record for the 12 months ended June 30th, no later than August 31st of each year. The Fund’s voting record is available (i) without charge, upon request, by calling the Fund toll-free at 1.800.525.7048, and (ii) in the Form N-PX filing on the SEC’s website at www.sec.gov.

     The Fund files its complete schedule of portfolio holdings with the SEC for the first quarter and the third quarter of each fiscal year on Form N-Q. The Fund’s Form N-Q filings are available on the SEC’s website at http://www.sec.gov. Those forms may be reviewed and copied at the SEC’s Public Reference Room in Washington, D.C. Information on the operation of the Public Reference Room may be obtained by calling 1-800-SEC-0330.

Householding—Delivery of Shareholder Documents

This is to inform you about OppenheimerFunds’ “householding” policy. If more than one member of your household maintains an account in a particular fund, OppenheimerFunds will mail only one copy of the fund’s prospectus, annual and semian-nual report and privacy policy. The consolidation of these mailings, called householding, benefits your fund through reduced mailing expense, and benefits you by reducing the volume of mail you receive from OppenheimerFunds. Householding does not affect the delivery of your account statements.

     Please note that we will continue to household these mailings for as long as you remain an OppenheimerFunds shareholder, unless you request otherwise. If you prefer to receive multiple copies of these materials, please call us at 1.800.CALL-OPP (225-5677). You may also notify us in writing or via email. We will begin sending you individual copies of the prospectus, reports and privacy policy within 30 days of receiving your request to stop householding.

18   |   OPPENHEIMER MAIN STREET OPPORTUNITY FUND

Item 2. Code of Ethics.

Not applicable to semiannual reports.

Item 3. Audit Committee Financial Expert.

Not applicable to semiannual reports.

Item 4. Principal Accountant Fees and Services.

Not applicable to semiannual reports.

Item 5. Audit Committee of Listed Registrants

Not applicable.

Item 6. Schedule of Investments.

a) Not applicable.

b) Not applicable.

Item 7. Disclosure of Proxy Voting Policies and Procedures for Closed-End Management Investment Companies.

Not applicable.

Item 8. Portfolio Managers of Closed-End Management Investment Companies.

Not applicable.

Item 9. Purchases of Equity Securities by Closed-End Management Investment Company and Affiliated Purchasers.

Not applicable.

Item 10. Submission of Matters to a Vote of Security Holders.

The Fund’s Governance Committee Provisions with Respect to Nominations of Directors/Trustees to the Respective Boards

1.

The Fund’s Governance Committee (the “Committee”) will evaluate potential Board candidates to assess their qualifications. The Committee shall have the authority, upon approval of the Board, to retain an executive search firm to assist in this effort. The Committee may consider recommendations by business and personal contacts of current Board members and by executive search firms which the Committee may engage from time to time and may also consider shareholder recommendations. The Committee may consider the advice and recommendation of the Funds’ investment manager and its affiliates in making the selection.

2.

The Committee shall screen candidates for Board membership. The Committee has not established specific qualifications that it believes must be met by a trustee nominee. In evaluating trustee nominees, the Committee considers, among other things, an individual’s background, skills, and experience; whether the individual is an “interested person” as defined in the Investment Company Act of 1940; and

whether the individual would be deemed an “audit committee financial expert” within the meaning of applicable SEC rules. The Committee also considers whether the individual’s background, skills, and experience will complement the background, skills, and experience of other nominees and will contribute to the Board. There are no differences in the manner in which the Committee evaluates nominees for trustees based on whether the nominee is recommended by a shareholder.

3. The Committee may consider nominations from shareholders for the Board at such times as the Committee meets to consider new nominees for the Board. The Committee shall have the sole discretion to determine the candidates to present to the Board and, in such cases where required, to shareholders. Recommendations for trustee nominees should, at a minimum, be accompanied by the following:

• the name, address, and business, educational, and/or other pertinent background of the person being recommended;

• a statement concerning whether the person is an “interested person” as defined in the Investment Company Act of 1940;

• any other information that the Funds would be required to include in a proxy statement concerning the person if he or she was nominated; and

• the name and address of the person submitting the recommendation and, if that person is a shareholder, the period for which that person held Fund shares.

	The recommendation also can include any additional information which the person submitting it believes would assist the Committee in evaluating the recommendation.
4.	Shareholders should note that a person who owns securities issued by Massachusetts Mutual Life Insurance Company (the parent company of the Funds’ investment adviser) would be deemed an “interested person” under the Investment Company Act of 1940. In addition, certain other relationships with Massachusetts Mutual Life Insurance Company or its subsidiaries, with registered broker-dealers, or with the Funds’ outside legal counsel may cause a person to be deemed an “interested person.”
5.	Before the Committee decides to nominate an individual as a trustee, Committee members and other directors customarily interview the individual in person. In addition, the individual customarily is asked to complete a detailed questionnaire which is designed to elicit information which must be disclosed under SEC and stock exchange rules and to determine whether the individual is subject to any statutory disqualification from serving as a trustee of a registered investment company.

Item 11. Controls and Procedures.

Based on their evaluation of the registrant’s disclosure controls and procedures (as defined in rule 30a-3(c) under the Investment Company Act of 1940 (17 CFR 270.30a-3(c)) as of 01/31/2009, the registrant’s principal executive officer and principal financial officer found the registrant’s disclosure controls and procedures to provide reasonable assurances that information required to be disclosed by the registrant in the reports that it files under the Securities Exchange Act of 1934 (a) is accumulated and communicated to registrant’s management, including its principal executive officer and principal financial officer, to allow timely decisions regarding required disclosure, and (b) is recorded, processed, summarized and reported, within the time periods specified in the rules and forms adopted by the U.S. Securities and Exchange Commission.

There have been no changes in the registrant’s internal controls over financial reporting that occurred during the registrant’s second fiscal quarter of the period covered by this report that have materially affected, or are reasonably likely to materially affect, the registrant’s internal control over financial reporting.

Item 12. Exhibits.

(a) (1)     Not applicable to semiannual reports.

(2)	Exhibits attached hereto.
(3)	Not applicable.

(b) Exhibit attached hereto.

SIGNATURES

Pursuant to the requirements of the Securities Exchange Act of 1934 and the Investment Company Act of 1940, the registrant has duly caused this report to be signed on its behalf by the undersigned, thereunto duly authorized.

Oppenheimer Main Street Opportunity Fund
By:	/s/ John V. Murphy
	John V. Murphy
	Principal Executive Officer

Date: 03/12/2009 

Pursuant to the requirements of the Securities Exchange Act of 1934 and the Investment Company Act of 1940, this report has been signed below by the following persons on behalf of the registrant and in the capacities and on the dates indicated.

By:	/s/ John V. Murphy
	John V. Murphy
	Principal Executive Officer

Date: 03/12/2009 

By:	/s/ Brian W. Wixted
	Brian W. Wixted
	Principal Financial Officer

Date: 03/12/2009 

EX-99.CERT

Exhibit 99.CERT

Section 302 Certifications

CERTIFICATIONS

I, John V. Murphy, certify that:

1.	I have reviewed this report on Form N-CSR of Oppenheimer Main Street Opportunity Fund;
2.	Based on my knowledge, this report does not contain any untrue statement of a material fact or omit to state a material fact necessary to make the statements made, in light of the circumstances under which such statements were made, not misleading with respect to the period covered by this report;
3.	Based on my knowledge, the financial statements, and other financial information included in this report, fairly present in all material respects the financial condition, results of operations, changes in net assets, and cash flows (if the financial statements are required to include a statement of cash flows) of the registrant as of, and for, the periods presented in this report;
4.	The registrant’s other certifying officer and I are responsible for establishing and maintaining disclosure controls and procedures (as defined in Rule 30a-3(c) under the Investment Company Act of 1940) and internal control over financial reporting (as defined in Rule 30a-3(d) under the Investment Company Act of 1940) for the registrant and have:

(a)	Designed such disclosure controls and procedures, or caused such disclosure controls and procedures to be designed under our supervision, to ensure that material information relating to the registrant, including its consolidated subsidiaries, is made known to us by others within those entities, particularly during the period in which this report is being prepared;
(b)	Designed such internal control over financial reporting, or caused such internal control over financial reporting to be designed under our supervision, to provide reasonable assurance regarding the reliability of financial reporting and the preparation of financial statements for external purposes in accordance with generally accepted accounting principles;
(c)	Evaluated the effectiveness of the registrant’s disclosure controls and procedures and presented in this report our conclusions about the effectiveness of the disclosure controls and procedures, as of a date within 90 days prior to the filing date of this report based on such evaluation; and
(d)	Disclosed in this report any change in the registrant’s internal control over financial reporting that occurred during the second fiscal quarter of the period

covered by this report that has materially affected, or is reasonably likely to materially affect, the registrant’s internal control over financial reporting; and

5. The registrant’s other certifying officer and I have disclosed to the registrant’s auditors and the audit committee of the registrant’s board of Trustees (or persons performing the equivalent functions):

(a)	All significant deficiencies and material weaknesses in the design or operation of internal control over financial reporting which are reasonably likely to adversely affect the registrant’s ability to record, process, summarize, and report financial information; and
(b)	Any fraud, whether or not material, that involves management or other employees who have a significant role in the registrant’s internal control over financial reporting.

Date: 03/12/2009

/s/ John V. Murphy  

John V. Murphy 

Principal Executive Officer 

Exhibit 99.CERT

Section 302 Certifications

CERTIFICATIONS

I, Brian W. Wixted, certify that:

1.	I have reviewed this report on Form N-CSR of Oppenheimer Main Street Opportunity Fund;
2.	Based on my knowledge, this report does not contain any untrue statement of a material fact or omit to state a material fact necessary to make the statements made, in light of the circumstances under which such statements were made, not misleading with respect to the period covered by this report;
3.	Based on my knowledge, the financial statements, and other financial information included in this report, fairly present in all material respects the financial condition, results of operations, changes in net assets, and cash flows (if the financial statements are required to include a statement of cash flows) of the registrant as of, and for, the periods presented in this report;
4.	The registrant’s other certifying officer and I are responsible for establishing and maintaining disclosure controls and procedures (as defined in Rule 30a-3(c) under the Investment Company Act of 1940) and internal control over financial reporting (as defined in Rule 30a-3(d) under the Investment Company Act of 1940) for the registrant and have:

(a)	Designed such disclosure controls and procedures, or caused such disclosure controls and procedures to be designed under our supervision, to ensure that material information relating to the registrant, including its consolidated subsidiaries, is made known to us by others within those entities, particularly during the period in which this report is being prepared;
(b)	Designed such internal control over financial reporting, or caused such internal control over financial reporting to be designed under our supervision, to provide reasonable assurance regarding the reliability of financial reporting and the preparation of financial statements for external purposes in accordance with generally accepted accounting principles;
(c)	Evaluated the effectiveness of the registrant’s disclosure controls and procedures and presented in this report our conclusions about the effectiveness of the disclosure controls and procedures, as of a date within 90 days prior to the filing date of this report based on such evaluation; and
(d)	Disclosed in this report any change in the registrant’s internal control over financial reporting that occurred during the second fiscal quarter of the period

covered by this report that has materially affected, or is reasonably likely to materially affect, the registrant’s internal control over financial reporting; and

5. The registrant’s other certifying officer and I have disclosed to the registrant’s auditors and the audit committee of the registrant’s board of Trustees (or persons performing the equivalent functions):

(a)	All significant deficiencies and material weaknesses in the design or operation of internal control over financial reporting which are reasonably likely to adversely affect the registrant’s ability to record, process, summarize, and report financial information; and
(b)	Any fraud, whether or not material, that involves management or other employees who have a significant role in the registrant’s internal control over financial reporting.

Date: 03/12/2009

/s/ Brian W. Wixted  

Brian W. Wixted 

Principal Financial Officer 

EX-99.906CERT

EX-99.906CERT

Section 906 Certifications

CERTIFICATION PURSUANT TO 18 U.S.C SECTION 1350,
AS ADOPTED PURSUANT TO
SECTION 906 OF THE SARBANES-OXLEY ACT OF 2002

John V. Murphy, Principal Executive Officer, and Brian W. Wixted, Principal Financial Officer, of Oppenheimer Main Street Opportunity Fund (the “Registrant”), each certify to the best of his knowledge that:

1.	The Registrant’s periodic report on Form N-CSR for the period ended 01/31/2009 (the “Form N-CSR”) fully complies with the requirements of Section 15(d) of the Securities Exchange Act of 1934, as amended; and
2.	The information contained in the Form N-CSR fairly presents, in all material respects, the financial condition and results of operations of the Registrant. This certification is being furnished to the Commission solely pursuant to 18 U.S.C. § 1350 and is not being filed as part of the Form N-CSR filed with the Commission.

Principal Executive Officer	Principal Financial Officer
Oppenheimer Main Street Opportunity Fund	Oppenheimer Main Street Opportunity Fund
/s/ John V. Murphy John V. Murphy	/s/ Brian W. Wixted Brian W. Wixted
Date: 03/12/2009	Date: 03/12/2009