A few bits:

* You can get away with buying just Windows Professional, and not Ultimate (there's not enough benefit to Ultimate IMHO to make it worth the jump in cost - Windows 7 Pro has XP Mode (a compatibility mode) built in, whereas the home versions do not.

* If you're stuck with using any version of Windows, 7 is the way to go - it is what Vista had been promised to be. To Microsoft's credit, they made UAC less annoying, memory management actually works, and you don't get sent to drive hell

• All this said, I have actually seen, in the two months I've used Windows 7 on my work laptop so far:
              - two BSODs (one kicked in when opening VMWare vSphere client, the second playing a flash game in Firefox).
              - one complete reinstall (KMS/Key Management System had corrupted, and refused to re-validate after fixing the corruption). Shifted from Win7 Enterprise to Win7 Professional.

• FWIW, in testing I've found that DAZ|Studio runs rather nice on Windows 7, but refused to run worth a damn under Vista on the exact same laptop.

IMHO? If I had the choice and the cash, I'd have a MacBook Pro (and if this upcoming bonus is big enough, that's exactly what I'm gonna get  :)  )