There are some good things about Windows 8 but oh man, they seemed to have lost the plot a little and the result is a bit of a mess for both desktop AND tablet users.
You absolutely need to get the Start8 app to make the desktop usable unless you want the Fisher Price experience. Even if you like that and the metro apps, the fact that the dual screen support is a mess destroys all usability.
They really need a big switch that you can flick to say "open apps in the desktop version". Really, clicking on a 48px PNG to look at it and having it open on a full-screen app that doesn't allow switching monitors or even going to the first or next image is inexcusable.
It's like they focused too much on getting a tablet OS and then forgot about the majority of power users who liked things as they were. Other vendors have a separate OS for tablet and for desktop. I can see the attraction of having a single OS for both but I think it needs a lot more work.
A lot of the issues are fixable though and just need tweaking and probably a good service pack. It's nice having Hyper-V on the desktop for VMs and it's good getting rid of the overly-complex translucent windows (although they still have it on the taskbar and it's a bitch to turn off). For $39.99 it's an OK upgrade but I wouldn't go out of my way to recommend it to anyone right now.