I have been currently playing WoW on my XP partition and the GPU gets about 68C and both of the CPU cores get about 55C when playing. I have found the game runs MUCH COOLER when on XP. The fans are going about 3500rpm average, I am also using a Targus chill pad. I play WoW on medium settings and capped the fps at 30.
I realize this is besides the point of this thread but WoW is the only real game I play on OSX . I'd really resist installing it on Windows.