EXHIBIT 8.1


                  [OPINION OF DAVIS POLK & WARDWELL REGARDING
                   MATERIAL FEDERAL INCOME TAX CONSEQUENCES]



                             Davis Polk & Wardwell
                              450 Lexington Avenue
                            New York, New York 10017
                                  212-450-4000





                                                    May 14, 2002


Comcast Corporation
1500 Market Street
Philadelphia, Pennsylvania 19102

Ladies and Gentlemen:


     We have acted as counsel to Comcast Corporation, a Pennsylvania corporation
("COMCAST"), in connection with (i) the proposed Mergers, as defined and
described in the Agreement and Plan of Merger dated as of December 19, 2001
among AT&T Corp., a New York corporation, AT&T Broadband Corp., a Delaware
corporation and a wholly owned subsidiary of AT&T, Comcast, AT&T Comcast
Corporation, a Pennsylvania corporation ("PARENT"), AT&T Broadband Acquisition
Corp., a Delaware corporation and a wholly owned subsidiary of Parent and
Comcast Acquisition Corp., a Pennsylvania corporation and a wholly owned
subsidiary of Parent and (ii) the preparation and filing of the related
Registration Statement on Form S-4 (the "REGISTRATION STATEMENT"), which
includes the Joint Proxy Statement/Prospectus (the "JOINT PROXY
STATEMENT/PROSPECTUS"), filed with the Securities and Exchange Commission (the
"COMMISSION") under the Securities Act of 1933, as amended (the "SECURITIES
ACT") and the Exchange Act of 1934, as amended.




     We hereby confirm that the discussion set forth under the caption "Material
Federal Income Tax Consequences" in the Joint Proxy Statement/Prospectus
insofar as it relates to the material United States federal income tax
consequences of the Mergers constitutes our opinion as to the material United
States federal income tax consequences of the Mergers, subject to the
qualifications set forth in such discussion.


                                        2


COMCAST CORPORATION                                                 May 14, 2002








     In accordance with the requirements of Item 601(b)(23) of Regulation S-K
under the Securities Act, we hereby consent to the discussion of this opinion in
the Joint Proxy Statement/Prospectus, to the filing of this opinion as an
exhibit to the Registration Statement and to the reference to our firm under the
headings "Material Federal Income Tax Consequences" and "Legal Matters" in the
Joint Proxy Statement/Prospectus. In giving such consent, we do not thereby
admit that we are in the category of persons whose consent is required under
Section 7 of the Securities Act or the rules and regulations of the Commission
thereunder.

     This opinion is being provided to you solely in connection with the
Registration Statement and may not be relied upon, circulated, quoted or
otherwise referred to for any other purpose.

                                          Very truly yours,


                                          /s/ Davis Polk & Wardwell