Used on recently, wasn't impressed by much. OS X LOOKS nice...wouldn't say its functionality was any more intuitive or fluid than Windows, and the first time I used OSX I got a kernel panic (this on a freshly imaged ibook), so I'm not sure if the stability is really much better than XP either.
The hardware again LOOKS nice but doesn't strike me as anything impressive beyond skin-deep. The only apple piece of hardware I'd consider buying is the Powerbook since I like its wide-aspect 15.2" screen and it's fairly compact for what it offers. But if it weren't for my friend working for apple and getting me a 25% discount, I wouldn't even consider buying that.