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                                                                     EXHIBIT 2.3


                               FIRST AMENDMENT TO
                          AGREEMENT AND PLAN OF MERGER


        This First Amendment (the "Amendment") to that certain Agreement and
Plan of Merger dated September 25, 2001, by and among Loudeye Technologies,
Inc., (now known as Loudeye Corp.) Ignition Acquisition, Inc., and Activate.net
Corporation, and solely with respect to Sections 2.1(c), 5.2, 5.3 and 5.5 and
Article VII, CMGI, Inc. (the "Agreement") is entered into as of the 12th day of
August, 2002. Capitalized terms not otherwise defined herein shall have the
meanings ascribed to them in the Agreement.

        WHEREAS, the parties now desire to amend the Agreement.

        In consideration of the foregoing, the parties hereby amend the
Agreement as follows:

        1.     Section 2.1(c)(i)(B) shall be amended in its entirety as follows:

               "(B) the right to receive the cash portion and the Deferred
               Shares (as defined in Section 2(c)(ii)(A) of the Agreement)
               portion of the Anniversary Payment on the dates set forth below,
               each such date being an "ANNIVERSARY DATE": (I) the cash portion
               of the Anniversary Payment shall be wired to CMGI for receipt on
               October 1, 2002, and (II) the Deferred Shares portion of the
               Anniversary Payment shall, on the date hereof, be directed to be
               delivered by Loudeye's transfer agent to CMGI.

        2.     The first sentence of Section 2.1(c)(ii)(A) shall be deleted in
               its entirety and replaced with the following:

               "ANNIVERSARY PAYMENT" shall mean: (I) with respect to the cash
               portion of the Anniversary Payment, Two Million Dollars
               ($2,000,000); provided, however, that if the wire transfer
               relating to the cash portion of the Anniversary Payment is not
               initiated by Loudeye on or prior to October 3, 2002, the cash
               portion of the Anniversary Payment shall be Two Million Two
               Hundred Thousand Dollars ($2,200,000), and (II) with respect to
               the Deferred Shares portion of the Anniversary Payment, One
               Million (1,000,000) shares of Loudeye Common Stock. Within Two
               (2) business days following the execution of this Amendment,
               Loudeye shall establish a segregated account and shall fund such
               account with the cash portion of the Anniversary Payment, and
               Loudeye shall maintain such account until the Anniversary Date
               related to the cash portion of the Anniversary Payment. The
               certificate(s) representing the Deferred Shares portion of the
               Anniversary Payment shall bear the following restrictive legend:

               THE SECURITIES HAVE NOT BEEN REGISTERED UNDER THE SECURITIES ACT
               OF 1933 (THE "ACT"), OR ANY STATE SECURITIES LAWS. THE SECURITIES
               REPRESENTED BY THIS CERTIFICATE MAY NOT BE OFFERED, SOLD,
               ASSIGNED, PLEDGED, OR OTHERWISE

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               TRANSFERRED UNLESS REGISTERED OR QUALIFIED PURSUANT TO THE
               PROVISIONS OF THE ACT AND APPLICABLE STATE SECURITIES LAWS, OR AN
               OPINION OF COUNSEL REASONABLY SATISFACTORY TO THE ISSUER IS
               DELIVERED TO THE ISSUER STATING THAT SUCH OFFER, SALE,
               ASSIGNMENT, PLEDGE, OR TRANSFER IS EXEMPT FROM SUCH REGISTRATION
               OR QUALIFICATION. NOTWITHSTANDING THE FOREGOING, SUBJECT TO THAT
               CERTAIN REGISTRATION RIGHTS AGREEMENT BETWEEN LOUDEYE
               TECHNOLOGIES, INC. AND CMGI, INC. DATED AS OF SEPTEMBER 25, 2001,
               THE SECURITIES REPRESENTED BY THIS CERTIFICATE SHALL NOT BE
               OFFERED, SOLD, ASSIGNED, PLEDGED, OR OTHERWISE TRANSFERRED UNTIL
               TWELVE MONTHS FOLLOWING THE DATE OF ISSUANCE BY LOUDEYE CORP. OF
               THIS CERTIFICATE.

        In the event of any inconsistency between the terms of this Amendment
and the terms of the Agreement, the terms of this Amendment shall control.
Except as amended hereby, the Agreement remains in full force and effect. This
Amendment may be executed in counterparts, including by facsimile, each of which
shall be deemed an original, but all of which when taken together shall
constitute one and the same instrument.

        IN WITNESS WHEREOF, the parties hereto have caused this Amendment to be
executed as of the date set forth above.

                                     LOUDEYE CORP.


                                     By: /s/
                                         ---------------------------------------
                                     Name:  John T. Baker IV
                                     Title: Chairman and Chief Executive Officer


                                     ACTIVATE.NET CORPORATION


                                     By: /s/
                                         ---------------------------------------
                                     Name: John T. Baker IV
                                     Title: President and CEO


                                     IGNITION ACQUISITION, INC.,


                                     By: /s/
                                         ---------------------------------------


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                                     Name: John T. Baker IV
                                     Title: Chief Executive Officer


                                     CMGI, INC.


                                     By: /s/
                                         ---------------------------------------
                                     Name: Thomas Oberdorf
                                     Title: Chief Financial Officer



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