1) Using the upgrade invalidates your XP key, so you cannot legally reinstall XP after you realize Vista was a huge waste of money.
I believe it has already been proved that this is not true.
2) It does not offer any performance increases over XP at all. There are absolutely no benchmarks out there that show any increase. In my personal experience with it, it is orders of magnitude slower than XP. It takes minutes to transfer relatively small files [~100MB] from one disk to another. The UI [Aero] can be very taxing even though it really doesn't offer that many effects. Beryl & Java3D desktop offer many more and detailed effects that will run smoothly with much lower requirements.
Not 100% sure but I think Aero is all loaded onto the GPU. I had no issues with performance in either XP or Vista so its difficult for me to judge that one. I am shocked though that the Xbox 360 has higher specs than the Xbox, I thought it was just a new OS in a shiny box.
3) DRM. If you don't know why this is bad, then maybe you should read some more
about it.
A tough one really, but then you could moan at anyone else that makes a next generation media platform, its a requirement although its not likely to ever be used because any distributer that uses it will face a huge publish backlash when DRM affects how we view our media. I steer clear of purchasing music these days after x64 and MSN music screwed me around so much. DRM inside Vista itself? Can't think I have come across it really out of the box.
4) UAC, to quote Hencry Spencer "Those who do not understand Unix are condemned to reinvent it, poorly."
Disable it, if you can't figure out how, you are actually one of the people that need to use it. If you do, after a few weeks when your configuration and installations are done re-enable it and see how much it does actually get in the way.
5) AutoCAD does not offer a version that is compatible with Vista and wont offer a service pack to fix it, that means your $4,000 software will not work until 2008 is released and you have to pay for an upgrade. That is a personal problem since I use AutoCAD daily.
Like you said, alot of 3rd party vendors need time to catch up, was the same with XP when we are started out on this site and its exciting times with lots of software updates, or frustrating if there aren't.
I love Vista but I do have problems with it and I am enjoying working them out, as far as $400 being too expensive for the Ultimate? Most likely but its the version for the person that wants everything so people should be looking at Home Premium as the top one and looking for the extra stuff they might need in Home Server later this year.
MS did actually also say that their biggest competitor in the OS market was XP and alot of work has been done to make various new stuff, built from teh ground up, work like XP.
