Well seeing as how we have a list of working AV for Windows 8, might as well start one for working games. If you want to contribute, feel free to do so!
Windows 8 Developer Preview Build 8102.
GREEN = Working
RED = Not working
BLUE = Additional information
Age of Empires 3 - Gives compatibility warning when starting age3.exe, but game works flawlessly if you ignore it.
Perfect World International
Rome: Total War
Team Fortress 2 - (Reported by iliveinabucket)
The Sims 3
World of Warcraft: Cataclysm