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                                                                   EXHIBIT 10.78

                       Shareholder's Voting Rights Proxy Agreement-Participation
                                                    Letter of Shanghai On-Target

                   ACKNOWLEDGEMENT LETTER FOR PARTICIPATION OF
                   SHAREHOLDERS' VOTING RIGHTS PROXY AGREEMENT

SHANGHAI FOCUS MEDIA ADVERTISEMENT CO., LTD., (registered address: Room 1003 F,
No.1027, Changning Road, Changning District, Shanghai) and JIMMY WEI YU
(Identity Card Number: 310106731015081) (hereinafter the "PARTICIPATING
SHAREHOLDER"), and SHANGHAI ON-TARGET ADVERTISEMENT CO., LTD. (registered
address: Room 1003H, No. 1027 Changning Road, Changning District, Shanghai)
(hereinafter the "PARTICIPATED TARGET COMPANY"), as independent party, hereby
agree to participate in the Shareholders' Voting Rights Proxy Agreement among
Focus Media Technology (Shanghai) Co., Ltd. (hereinafter "FOCUS MEDIA
TECHNOLOGY"), Shanghai Focus Media Advertisement Co., Ltd. and other relevant
parties (hereinafter the "PROXY AGREEMENT") dated March 28 2005. Participating
Shareholder and Participated Target Company agree to entrust the Trustees
designated by Focus Media Technology to exercise the voting rights in
Participated Target Company in respect of 100% of the equity interest in the
registered capital of Participated Target Company held by the Participating
Shareholder as of the date of this Acknowledgement Letter, on behalf of
Participating Shareholder.

Once this Acknowledgement Letter is executed by the Participating Shareholder
and Participated Target Company, Participating Shareholder and Participated
Target Company shall be deemed to have made the same undertakings and warranties
with those of the Shareholders and Target Companies under the Proxy Agreement
(to the extent that is related and applicable to Participating Shareholder and
Participated Target Company), agreed to respectively perform the obligations of
the Shareholders and Target Companies stipulated in the Proxy Agreement (to the
extent that is related and applicable to Participating Shareholder and
Participated Target Company), and acknowledged the rights and obligations of the
Parties under the Proxy Agreement.

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                       Shareholder's Voting Rights Proxy Agreement-Participation
                                                    Letter of Shanghai On-Target

                                [EXECUTION PAGE]

SHANGHAI FOCUS MEDIA ADVERISEMENT CO., LTD.
(Company chop)

Signature by:    /s/ Jason Nanchun Jiang
              -----------------------------
Name: Jason Nanchun Jiang
Position: Authorized Representative
Date: May 22, 2006

JIMMY WEI YU

Signature by:    /s/ Jason Nanchun Jiang
              -----------------------------
Date: May 22, 2006

SHANGHAI ON-TARGET ADVERTISEMENT CO., LTD.
(Company chop)

Signature by:    /s/ Jason Nanchun Jiang
              -----------------------------
Name: Jason Nanchun Jiang
Position: Authorized Representative
Date: May 22, 2006

FOCUS MEDIA TECHNOLOGY (SHANGHAI) CO., LTD.
(Company chop)

Signature by:    /s/ Jason Nanchun Jiang
              -----------------------------
Name: Jason Nanchun Jiang
Position: Authorized Representative
Date: May 22, 2006