The basic install of Windows Vista was uneventful, althought it did required about 4 reboots and about 1 hour to complete. Once the install was complete the functionality, including things like Aero Glass were there without any special work. To get the drivers specific to the Apple hardware (especially thing like wireless and bluetooth) I did install the drivers from the current version of the Boot Camp Assistant
The Vista installation was based on the 32-bit version which still is likely the common version deployed. The benefits of the 64-bit version (other than addressing the memory issue mentioned earlier is not really clear.
After running the Performance test under Vista the score ended up at 4.0. This actually went down fom 4.3 after initial install due to poorer graphics performance. Leading me to believe the native Windows drivers did better with the 7300GT NVidia card than the Apple drivers installed by boot camp.
So with Mac OS 10.4, 10.5, Windows XP and Vista the Mac Pro is now capable of the Quad booting operating systems. It will be interesting to see which one (if any) produces better performance.
But next … OS madness with Parallels and VMware in the OS within and OS department.