I originally switched windows to mac three years ago, prompted by the hideous torment of digital video capture/editing/DVD burning under windows 2000 at the time. I only began digital still image processing after the switch, so I don't know what it would have been like under any flavor of Windows.
Video on the Mac is a snap; the iLife software that gives you iDVD and iMovie are excellent for all but hi-end pro stuff; I have fewer hardware / driver issues under MacOS but find that OS upgrades are just as painful.
I plan to stick with Mac; looking forward to faster performance upgrades once they migrate to Intel processors.