I just installed OS X on my PC [Hackintosh
] to try out some iPhone development. Its my first experience with it after years of Windows and I have to say I can't really see what the big deal is about. People talk about it being the second coming in terms of usability and the only thing I could say is noticeably better is the indexed file system which gives very fast searching.
As for the reliability, just try installing it on non-standard hardware and you see why Apple can make a trouble free user experience - by standardizing the hardware. You can install Windows on billions of combinations of hardware setups and nearly all of the time it'll still work. Running OS X on my PC I get about 2 hours before it will definitely lock up, playing a video in iTunes is instant lockup etc. I mean this comes with the territory when doing this sort of thing but makes you appreciate Windows.
I've just tried Windows 7 Beta on my laptop and that is flat out awesome. Huge improvment over Vista, which I never switched to on my home machine as I didn't feel that it offered anything worthwhile.