Microsoft just released Vista to MSDN yesterday. Today I did an install on my main PC, the install went smooth and was the quickest install of Vista. Two issues will keep me from using it Creative has no drivers for my sound card yet and Titan Quest won't install. The first issue means I can't play music while I work or listen to the sound on YouTube videos. The second not as major but still a pain, I suspect it is the copy protection not working rather than any issues with the game.
I also tried to install Vista on my HP laptop but for some reason the DVD drive is not recognizing the disk as bootable. Which is kind of funny since that was the machine that made the disc.
One new thing I tried with this install is the user I was using most of the time was only a user and not an administrator. This made the access checks even worse as I had to provide an administrative account and password for every second click. This would become less of a pain once things are installed and setup correctly.