crypt,
I had a chance to experiment with Windows 8 a little bit on a really old workstation and so far my impressions are as following:
1) I do not like the "tablet" style GUI. Hopefully there's an option to disable it, as it is rather disorienting. The traditional Win 7 desktop is still there and it comes in and out as you switch between the applications. But the main theme has become the rather dull looking "touch-screen" friendly GUI.
2) I do like the driver recognition. They seem to have upgraded the hardware detection engine as it is a lot smarter and has found almost every single driver needed for our machine.
3) Speed. It is significantly faster than Windows 7 running on very old equipment. I expected it to lag, but it didn't. Also, booting off of a 6 year old 5400RPM drive took only about 20-30 seconds.
In essence, it is very much Windows 7 with certain tweaks and upgrades that were needed. If they have avoided the new theme, I would've given it 9/10. So far, it's 8/10 because of the theme. If they give us an option to disable it altogether, it will be 9/10 in my book.