NATIONAL BROADCASTING COMPANY, INC.

                                                                       Exhibit 1


                             JOINT FILING AGREEMENT

         We, the signatories of the statement on Schedule 13D to which this
Agreement is attached, hereby agree that such statement is, and any amendments
thereto filed by any of us will be, filed on behalf of each of us.

Dated: December 10, 1999


                            GENERAL ELECTRIC COMPANY

                            By:      /s/ ▇▇▇▇▇▇ ▇. Healing
                                     --------------------
                            Name:    ▇▇▇▇▇▇ ▇. Healing
                            Title:   Attorney-in-Fact


                            NATIONAL BROADCASTING COMPANY HOLDING, INC.

                            By:     /s/ ▇▇▇▇ ▇. ▇▇▇▇▇
                                     --------------------
                            Name:    ▇▇▇▇ ▇. ▇▇▇▇▇
                            Title:   Vice President


                            NATIONAL BROADCASTING COMPANY,
                            INC.

                            By:     /s/ ▇▇▇▇ ▇. ▇▇▇▇▇
                                    --------------------
                            Name:    ▇▇▇▇ ▇. ▇▇▇▇▇
                            Title:   Executive Vice President









                            NBC MULTIMEDIA, INC.

                            By:     /s/ ▇▇▇▇▇▇ ▇. ▇▇▇▇▇▇▇▇▇
                                    --------------------
                            Name:    ▇▇▇▇▇▇ ▇. ▇▇▇▇▇▇▇▇▇
                            Title:  President


                            GE INVESTMENTS SUBSIDIARY, INC.

                            By:      /s/ ▇▇▇▇▇▇ ▇. Healing
                                     --------------------
                            Name:    ▇▇▇▇▇▇ ▇. Healing
                            Title:   Vice President