This excerpt taken from the CSGP DEF 14A filed Apr 30, 2007.
PROXY VOTING AND REVOCATION
You may vote by signing your proxy card, or if your shares are held in street name, by signing the voting instruction card included by your broker or nominee, and mailing it in the enclosed, postage prepaid and addressed envelope. If you properly complete and execute your proxy card and return it before the Annual Meeting:
You may revoke your proxy at any time before it is voted by:
Simply attending the Annual Meeting will not revoke your proxy. If you instructed a broker to vote your shares, you must follow your brokers directions for changing those instructions.