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It's not as bad as I though it would be. It is actually usable in one way or another, but still - it is not THAT kind of usability. Actually, it is now less usable than - say - Unity known from Ubuntu land ...
Congrats, Microsoft! you made it - you created early alpha UI and you're trying to convince people to actually use it.
I don't believe people will buy this new metro UI concept, but the "normal desktop" [kinda normal] thing saves Windows 8 ass a bit.