I've got Vista Ultimate installed on my Mac Pro, and I can't really complain about anything.
The Mac Pro is the best PC I've ever had, and it runs OS X as well
Actually, I use OS X all the time. I only boot to Windows when needed. But, I have the system fully loaded with all my software from my old PC, and it just flies in Windows. Sadly, I think some tasks in Windows seem to complete faster than they do in OS X. Hopefully Leopard will fix that.
I've gotten to working with my photos in Windows just because of the power of the photo editors that I have already. And, they seem to work much better than their comparable Mac counter-parts. But, of course I'm cheap. So, I haven't invested in the more expensive options available for the Mac. I've tried the cheapies, and the cheapies in OS X don't seem to do the stuff I need as well as the cheapies in Windows.
I'm sure if I threw more money at it, I'd find a suitable Mac program. But, for photo editing, my budget is FREE. So, there you go
The free PC software I use irons out my photo flaws better than the free OS X photo editing software I can find (of which there is little).
But, I've tinkered with making DVD's in Windows Vista using the built-in tools. And while not as nice as iLife '06 and iMovie 6, I think it works better than iMovie '08.
It encoded and burned the DVD for an hour movie in about 20 minutes on my Mac Pro. Pretty nice. I haven't used iMovie 6 and iDVD on the Mac Pro yet (I was just tinkering at the moment). But, I'll be starting on a major movie project soon, so I'll get to see how much faster iLife '06 is compared to when I ran it on my G5 pretty soon.
Seriously, the absolute only complaint I have about Vista on the Mac is the lack of a CD eject button on the front of the computer. In Vista, I have to go to the Computer drives screen, and then click eject. I know the reason is that Vista anticipates a computer with a built-in eject button to open the drive.
Otherwise, no complaints. Vista is fast, beautiful, and reliable on my Mac.
Now, if only it would run my OS X programs, then it would be perfect.
It is nice to have my Mac run Windows so well. I have removed two machines from my cluttered desk, and replaced them both with a single computer now.
When I need Windows, I just reboot. The Mac Pro runs Windows better than my old PC did
I also run Office 2007 Ultimate on the Mac in Vista Ultimate. And, Office just flies on this machine. No issues at all