vista isn't actually that bad (from sp1 atleast). I personally think its far more efficient to use than xp and apart from wishing for the occasional improvement in transfer speeds over my network to my nas (as much down to the nas as vista) I would rather use vista (x64) over xp any day of the week on my systems.
I haven't used windows 7 yet but am curious as to why you went for ultimate when pro is the same except for the languages from what I can gather.
I find using Windows 7 is a vast improvement on Vista! My main work PC never gets turned off, it has 4GB of RAM and running two 22" monitors on a Nvidia gfx card I have found no driver issues (a la first install of vista way back when).
The system runs stupid quick - i had vista on the same machine prior to installing Windows 7 (first time installed was about 7months ago i think).
All the software i run on a day to day basis runs fast and without issues. W7 has only crashed ONCE on my main machine but that was due to a hard drive failure (was on its way out for a while).
I used to and still do have (partition on machines) xp which has been tweaked to death to get the best performance possible.
Ignoring any speed gains from going x64 for x86 (this equates to about a third less time during a render for me) the overall os is more geared towards useability, the search is now more heavily integrated (improved more in w7) and if you want a program, file or whatever its just a case of type in a few letters usually rather than going through the whole menu (and I'm organised). Memory management is better, overall snappiness of the machine when loading a program etc is better due to the 'caching' of key programs. It's just faster but you don't notice it straight away (or explain why easily) - if you use vista for a few weeks (no xp) and then go back to xp you will feel that the os interface is just slower.
I will admit I downloaded tweakuac as that part of the new features annoyed the hell out of me.
I feel that Windows 7 is going to be very stable. I feel using it already beats the Vista OS. I still use another machine on XP however it has been around a while and everything has been patched up. I feel that Vista has never met my needs, I felt it was a very poor OS and I have never been a fan. Now I am on 7 i dont think Ill ever go back. Windows 7 is very good in organising open applications and usability is great. I used the BETA before this proper realease and that also was very Solid.
Vista is just different to xp, you need to spend a little while getting used to it and also give it a chance to take notice of your workflow, once thats done its overall speed improves quite dramatically, poor drivers on release really didn't help its cause though (nvidia were especially poor).
I've read on another forum that snow leopard has the same approach/problem, its slow for a while after its been installed while it scans the system but after that it speeds up.
My girlfriend has had a vista laptop for almost a year, it still gives her loads of grief.
So this doesn't get into a mac vs pc arguement, I think microsoft focussed on the GUI rather than considering the PC spec first, but then as we have all discussed, if I (well anyone) spent a grand on a PC, it would be mind blowing!
it could be down to all the bloatware thats added to the laptop, I built my rigs (with xp) and then upgraded to vista a little while after it came out.
Also has she done all the updates, but having said that even xp is slow id the wrong person gets hold of it.