Depending on when you were checking the Mac you may be able to get that Mac even cheaper since they bumped up the specs that morning. I'm not sure about the games, I haven't played a PC game for years, but if they would work OK with the integrated 950 chipset then it should be fine. Although you'd have to boot directly into Windows to make use of the acceleration, for now. Also I would highly recommend you DON"T buy the extra ram from apple. You can pick it up from crucial.com or newegg.com for a lot cheaper. It's cake to install a new HD or RAM on the MacBook also which is nice, both are accessible once you unlatch the battery.
Personally I'd go with a Mac instead of a PC :)
