> Tbh i'm starting to think that I do not see microsoft being able to keep it's position in the OS market

It's a big space. Traditionally, Microsoft has held both the multimedia, gaming and lots of professional segments, but with Valve doing a large push into the two first and Microsoft not even giving it a half-hearted try, it might just be that corporate computers continue using Microsoft, people's home media equipment is all Valve and hipsters (and others...) keep on using Apple.