All in all...lol...eventually XP, probably within next 5-10 years won't be the minimum spec anymore. Direct X 9 must also be nearing its end, like Jag said, Dx12 will probably change a lot of things. But then again, I think the economy is largely to blame for the lack of Dx10 and Dx11 games (Since they're obviosuly more expensive to produce and not many people now have killer PCs to run them).
I even just made this PC with Win7, and so far It's just like XP to me. I've had no issues and loved it (obviously skipped Vista). If you can make the jump to Win7 I think you'll be happy like me