Running Vista 32 bit Business at work since it came out, fresh install.
Running Vista 32 bit Home at home on my laptop, fresh install.
Running Vista 64 bit Business at home on my game machine, fresh install.

No issues doing technical work (network captures, programming, AD management, scripting and running virtual machines) or with any games (running Firefox for web games, non-administrative account for local games) on any of the systems. SP1 has awesome performance improvements for file system access; I'm waiting for the official release since both of my laptops are on the list for bad driver installers on the RTM version that will be fixed in the final version.

If UAC bugs you all of the time, you can choose to launch programs by default as an administrator by simply right clicking on the icon --> properties--> Compatibility tab --> Check the box under Privilege Level that says Run this program as an administrator. Issue solved. AUC is definitely worth the extra click or two for all the additional protection it gives you.

Good luck with whatever you pick.