At the risk of piling on, I'll join the chorus of those who wish Windows 7 Ultimate was, well, more ultimate--offering truly important features that aren't in other versions of the new OS. While I don't think having an "Ultimate" that really isn't will be the undoing of the House of Gates, I can tell you I won't be buying it.
I did, however, based on previous experience, purchase a copy of Windows Ultimate, because it was the upgrade for Windows XP Pro and required for the network I was running at the time. A business network I was running at home, mind you.
Having switched to a mix of Macs and PCs, I don't run that network anymore so Vista Ultimate doesn't get me anything and when I upgrade to Win7 it will mostly be by doing clean installs--that is if I upgrade my XP machines at all, which is becoming more and more doubtful.
Microsoft will have to prove to me that Win7 won't slow down my XP boxes before I will even consider upgrading. It's more likely, I think, that Win7 will arrive at whatever pace I replace older machines with newer hardware.
When I do that, I will be much more careful about choosing the proper version of Windows 7 with the new hardware than I have been in the past. I might be willing to go as far as Professinal, but the enterprise features that define Ultimate, such as BitLocker, drive encryption, aren't worth the money, at least not to me.
And, did I mention that Mac OS X comes with drive encryption as a standard feature included in the one-and-only version Apple sells to users? (I am not including the Mac OS Server since it's not a user OS).
I think Windows 7 may finally get Microsoft over the impasse that Vista created. My testing, and that conducted by those I trust, makes me look forward to its release. But, OS upgrades aren't nearly as important as they used to be and, without built-in apps to upgrade, Microsoft is at a disadvantage to Apple in getting my upgrade dollars.
The more I think about it, the less interested I am in doing any XP conversions to Windows 7. And if I can talk myself out of upgrading that easily, it's a bad sign for Microsoft.
The good news: I probably will be replacing some hardware and will be happy to find Windows 7 on-board. Windows 7 Professional, or less, that is.