Well, I just managed to get the Pre-RC1 (5536) build of Vista up and running, released at the end of this week. I had to get a hard disk replaced, and so gave up Beta 2 at the time, but the new drive is back.
Install time is cut in half from what Beta 2's was. The OS itself is also far snappier. It defaulted to Aero turned off on my machine since it now analyzes your system and makes decisions on how to set for best performance during install, but I turned Aero on, and it's still a lot faster than Beta 2 was in Aero mode. The SoundBlaster Live I added didn't install drivers on the first shot (had to go to Device Manager and tell Windows to search on the Web) but that's up and running now, but drivers for the game port on the card did not install properly.
My other issue so far is antivirus software. Avast! Antivirus 4.7 Free edition worked well witn Vista Beta 2; Build 5536 pops up a message stating there is a known compatibility issue, and the OS refuses to load the startup drivers/services. I've installed Trend Micro's Vista-capable beta of PC-Cillin; hopefully that will work, but the installer package is a whopping 83MB. I chose minimal install killing a lot of features I don't need/want, hopefully that will pare the program down. Even though I didn't install its personal firewall software, it turned off the Windows Firewall; looks like some bugfixes are in order.
Web browsing is downright snappy. I don't know what it is, but the build of IE7 loads some pages so quickly, it would seem as if they were already cached locally. I still hate Microsoft locating the Home/Options/Refresh buttons away from the Forward/Back buttons; this just seems idiotic in terms of user interface designs to me, and I'd prefer they were all back on the left, where I think they belong.
I'll be installing Office tomorrow. In the meantime, just an FYI - If you have a Vista Beta 2 key, it will work with Build 5536, including activation.