Question makes no sense. That's like saying will a sedan beat a coup. They have two different purposes. The Mac and PC share general purpose attributes which makes the Mac the better system for a variety of reasons ( lack of virus, ease-of-use, security, etc). The PC is a gamers' rig. An area Apple has not sold into. Naturally, gamers will prefer PCs. In certain applications such as MS Excel, the PC has the larger installed base.

Overall, if you measure the new comers onto the Mac or PC platforms, Apple is adding more users based on ipod, iphone, and other accessories sales. Mac Wins.