vista shmista; every release of M$ stuff gets worse.
Today for example we had a unique experience as we had a rush job on to make some updates to a WindowsCE build for a customer. So myself and a colleague got to work installing and configuring the correct version of CE Platform Builder (yet another excellent M$ product, not).
He has a mongo laptop and a mongo desktop - one is a Core Duo thingmy the other some massive AMD thing, plus RAID and terabytes of RAM, blah blah blah. Both running some flavour of XP. Meanwhile I refuse to use XP at work and run a proper operating system on my work machine and use QEMU to run VisualStudio 6 (the last useful version IMHO) when I have to. But Platform Builder is so mammoth that it runs too slowly under QEMU to be usable. Luckily I have an old Celeron 2GHz machine with 512MB RAM that I keep for office Quake tournaments with Windows 2000 and Quake on it (we just recently binned our last NT4 machine due to h/w failure, else I would have used that).
I installed Platform Builder on that in less time that he could on either machine, and my builds took less time too

That can only be caused by XP and it's layers of stuff .. the core OS is NT for W2K and XP alike.
My brother who is a hard core Windows programmer still refuses to use anything but Windows98 on his main machine - everything else is just too slow
So before you all go upgrading to Vista, remember that in the end, Firefox and Thunderbird will look just the same, and everything else might look pretty but will run slower and won't actually help you do what's important ...
Robin (dinosaur and proud of it)