Microsoft launched its Games for Windows marketing and certification program for PC games around the time of the Windows Vista OS launch. Since that time many publishers and developers have participated in the Games For Windows program but many others (most notably Valve, Blizzard and EA) have passed on offering their games for Games For Windows certification.
This week Microsoft announced new guidelines for developers and publishers to have their PC games certified for Games For Windows, including a way to certify their titles themselves. That should allow more PC games get that Games For Windows label. The new requirements were made in part to get PC games ready for the launch of Windows 7 next month. Games For Windows titles in Windows 7 must support the OS's parental control and ratings features, support for both 32-bit and 64-bit versions, and more.