I must say that I like Vista, I have been using it since the 5308 beta.
I am running it on an almost 3 year old Toshiba P15 laptop which can do the full aero experience and on a home built desktop which does not support aero so I use the classic interface.
In the begining the UAC was kind of annoying but that was when I was installing programs and doing general setup to get things the way that I like. But after everything was setup I hardly ever get UAC prompts from just using my computer in my daily routine.
The only real annoyance that I have is the slowness of doing operations on files such as copying, deleting or moving. But I solved that problem by doing these operations from the commandline.