I've tried 7 and while it's polished, I still prefer good (?) old XP. Win x64 still has a long way to go with drivers -- at least, I couldn't find sound drivers for 2/3 computers -- and the sound system itself seems to work against you as much as it possibly can. I also always experience a black screen and delay when alt-tabbing from WoW -- even with all the fluff turned off -- which never happens in XP.
Microsoft did well with this one, but it's still hard to find an actual reason to make the switch from XP. Sure, the initial setup is much quicker and again, more polished, but the experience doesn't best XP when it's all configured in my opinion.
Well, that's my two pence anyway
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