I've been running it now for about 3 months and after getting over the initial 'where did they put that?' phase in which you can't find things in the places you're used to (the Start menu shortcuts were a particular pain for a while as they are save in two different locations), I actually prefer it to XP. It looks nicer (admittedly a subjective judgment), boots faster (totally objective), and doesn't suffer from the same hardware limitations (if you run the 64-bit version). It may have been a dog when it came out but I learnt my lesson years ago and never upgrade to a new Microsoft operating system until there has been at least one service pack. I didn't get onto XP until service pack 2, by which time all was peachy, and moving to Vista 64 has been about as painless as it could have been. You can't blame Microsoft for the limitations of 32-bit operating systems, after all; I am actually rather impressed how much 32-bit stuff will run seamlessly in a 64-bit environment.
Only a handful of applications have misbehaved. Winamp was the one I miss most, but it's not like there are no other free mp3 players out there. Google desktop I also miss; I'm very surprised an organization of Google's size can't muster 64-bit support for a popular application like that. And I don't think Zone Alarm firewall yet exists in 64-bit form. Otherwise, I could transfer everything from my old XP installation. Virtually all my hardware (printer, scanner, joypad, USB phone, card reader etc.) also worked flawlessly; the only thing I had to retire was a webcam and it was some Taiwanese OEM product. Gaming is also generally not a problem; I have had issues with the new Riddick game and Galactic Civilizations, but I am not at all sure these are due to Vista itself. The most annoying thing has been the well-documented issues with user access control, which is best left turned off if you feel confident with your computing.
Windows 7 is well on the way but I see no need to change my current policy of waiting for at least one service pack before upgrading. I'm now very happy on Vista. I don't know what it was like when it first came out (though I can imagine; I did try the XP beta, one of the reasons I decided to leave it alone for a long time afterward), but now it's very usable, and it's almost a shame that it's acquired such a bad reputation.
subville
It uses 100% CPU pretty much ALL the time. I reckon I'd need about 5G of RAM and a much stronger CPU for it to cope smoothly