Its like windows vista... Its a "lets dip our feet in the water" sort of pull.
I would say its *very* preemptive to release it so shortly after people have just gotten used to Win7 and Win2008 R2. After playing with win8 and win2012, there's no way I can see either as any sort of viable OS. Trying to get people to use either is a very long jump - maybe its a long jump to see how much win8 will be used on tablets.
Win2012 is, to me, a disaster. There's no start button - instead you must mouse down to pixel 0,0 where there's nothing to indicate "hey - start button here" and when you do discover it, its like being given a camaro, only to discover that the V-8 has been pulled out and rigged with a 4 cylinder. There's also another hidden bar for "charms." Why all the hiding?
Hyper-V has improved a little, and there are some administrative functionality that, if you know how to get to, might be useful...
I just think its too soon - people are comfortable with Win7 and more importantly, have gotten comfortable with Win2008 R2, and how to manage each. Big corps are just now adopting Win7, and people tend to take their "work" home with them. They have gotten comfortable with the new OS, and IT people are stubborn.
And, lets face it - VMWare beat Microsoft to the VM punch, and that's where most small and medium, and especially large enterprises. Sure Win2012 is now manageable by one workstation, but we've been managing servers with RDP and VMware's native console passthrough for a long time.
I'm sure lots of other people have their opinions, so lets see those.