Wrong completely there are a lot of Mac users who are gamers also. Windows STINKS! They are prone to viruses and break down.Install windows on your mac that is more sensible.
as already said, saying windows stinks then saying install it makes no sense
secondly, having a mac won't prevent you from having viruses on the mac when running windows and the whole break down and repair isn't really true if you buy a quality laptop, PC's with the same specs but at half price is a bad comparison to the MBP, you need to compare something of better quality which can be had cheaper
also gaming on OSX doesn't seem to go over well, you need higher specs to get less FPS in games that are on both systems, even look at the requirements, even Source based games (Valve) don't fair well at all on OSX
I think steam would be a good place to start. Keep in mind that Mac's are a great computer but really lag in the field of gaming. There are just a handful good games that are on Mac's. I would suggest installing Windows as the second OS on your Mac. Then you get the good of both Mac OS X and Windows 7. I hope I was of some help.