As far as MS and games goes, I think that it is a circular thing. Most gamers use windows because all of the AAA games support windows on launch day and during open betas etc... Some of them don't support Linux so if you want to play all the latest and greatest games you run windows. Game devs keep developing for Windows because that is where the bulk of the users are.
I've heard from several people that either use Linux but have a separate windows PC for gaming or want to switch to Linux but only use windows because of gaming. As a " no tux no bux " gamer myself it is frustrating to hear stuff like that but I think that there is a silver lining... All that it is going to take is for one forced update to screw up gaming on windows during a release or huge patch from a big game. Say for example a game like world of Warcraft has a huge content patch and windows forces and update that screws up gaming for a day or two until they can patch around it, but during that time frame Linux users playing through wine are ok and they are the first to down certain bosses or something like that.
Just one big fuck up like that and I think we'd see a bunch of people give Linux an honest try. As a windows convert from about 3 years ago I can say that for me once I gave Linux an honest try there was no going back.