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                                                                   EXHIBIT 10.66

                                     Shareholders' Voting Rights Proxy Agreement
                                             Target Media Acknowledgement Letter

                   ACKNOWLEDGEMENT LETTER FOR PARTICIPATION OF
                   SHAREHOLDERS' VOTING RIGHTS PROXY AGREEMENT

SHANGHAI FOCUS MEDIA ADVERTISEMENT CO., LTD. (registered address: Room 1003F,
No. 1027, Changning Road, Changning District, Shanghai), SHANGHAI FOCUS MEDIA
ADVERTISING AGENCY CO., LTD., (registered address: Room A65, 28 Floor, No.369,
Jiangsu Road, Changning District, Shanghai) (hereinafter the "PARTICIPATING
SHAREHOLDERS" collectively), and SHANGHAI TARGET MEDIA CO., LTD. (registered
address: Room 2, No. 85, Xinsixi Street, Zhelin Town, Fengxian District,
Shanghai) (hereinafter the "PARTICIPATING 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 "PROXY AGREEMENT") dated March 28 2005.
Participating Shareholders and Participating Target Company agree to entrust the
Trustees designated by Focus Media Technology to exercise the voting rights in
Participating Target Company in respect of 100% of the equity interest in the
registered capital of Participating Target Company held by the Participating
Shareholder as of the date of the 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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                                     Shareholders' Voting Rights Proxy Agreement
                                             Target Media Acknowledgement Letter

                                [EXECUTION PAGE]

SHANGHAI FOCUS MEDIA ADVERTISEMENT CO., LTD.
(CHOP)

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

SHANGHAI FOCUS MEDIA ADVERTISING AGENCY CO., LTD.
(CHOP)

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

SHANGHAI TARGET MEDIA CO., LTD.
(CHOP)

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

FOCUS MEDIA TECHNOLOGY (SHANGHAI) CO., LTD.
(CHOP)

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