No.... just no
Pianoguy... your post sounds like you aren't upgrading simply because your computer can't handle it. Vista was made for computer that have been at least upgraded slightly in that past couple years.
This isn't Windows XP people.
And if I recall your statement: "Well, the more I read about Vista, the more it starts to look like XP "SP3" (but they get to charge for it)."
Well, duh.. what was XP? You can degrade XP down to look exactly like Windows 98. Same with Vista.
The UI will always remain the same, it will just have better toys to play with.