Saw this bit over at gamers.nl
Thanks for alerting us to the possible presence of a virus in the GameSpy Arcade Installer. We verified that the GameSpy Arcade Installer did indeed contain the W32.Nimda.E@mm virus shortly after receiving your e-mail. The infected file was immediately replaced with a virus-free version of the installer.
Your computer may be at risk of infection. Fortunately, the virus maybe easily removed by using this free tool from Symantec.
We thank you for your help in alerting us to this problem and hope that you enjoy using GameSpy Arcade.
Karen "Cobby" Cobb
Customer Service Manager
News source: Gamers.nl