OS X is just as bad as Vista.
I have at work a herd of Apples of all generations, starting from Quadras to G4's.
The IT manager has made the idiotic decision of trying to migrate them all to OS X. Dumb thing to do! First of all, the software versions (I mean Freehand, Illustrator, Photoshop and such) for OS 9, are not working in OS X. They won't even install for Christ's sake! Then, almost all the periferals are no good! 2 year old scanners do not have OS X drivers. Not even on the Internet. Same with printers. Same with drawing tablets. Furthermore, they will try to run on the Internet and upgrade instantly just like their MS counterpart. As to the stability... We've left one of the computers to download updates during the night and we've found it blocked to the point we had to reinstall the next morning.
No... APPLE OS X is no better than Vista! They're just plain 'ol crap! An OS is supposed to be just a simple application launcher, that would run on any computer...