Very good question indeed. I believe though, in the evolution of gaming and game makers, that the "brains" at Valve have taken one look at the "Windows Roadmap

Very good question indeed. I believe though, in the evolution of gaming and game makers, that the "brains" at Valve have taken one look at the "Windows Roadmap" and bet against it. Remeber that Windows 8 is the foundation of the "future" for microsoft. We going to see a massive shift in it's laws/legalities/processes for both gamers and game makers. The change won't be over night, yes, but it's inevitable. Given a "free", open platform is now realitvely stable, why not move to it and not have the headache of having to "conform"? I love linux. I don't mind Windows. If i have the option... it's an easy decision.