From what I've seen so far, it needs about twice as much memory as XP
does, in addition of course to a better display card, more disk space,
and faster CPU. Vista is supposed to have improved security, but I'm
already seeing Vista machines crawling with viruses and spyware.
If you have the upgrade edition and your operating system needs to
be reloaded, you cannot do it directly by booting from the installation
disc. You need to first reload your original operating system, then
run the Vista disc from it. (Have already gone through this excercise
and it's a real pain.)
Here is a non-flattering review from Forbes:
http://www.forbes.com/free_forbes/2007/0226/050.html
Some other bad things about Vista can be found at:
http://www.badvista.org
The consensus in the industry seems to be basically "nothing much to
see here." Unless you really, really like the eye candy, or are a
gamer who needes DirectX 10, there seems little reason to "upgrade"
an XP system to Vista.
That sounds about right.
It may have something to do with the fact that they are convicted
monopolists (check the findings of fact in the Microsoft case),
and have not been punished in any meaningful manner. They do it
because they can.