Cool, I’m playing Wipeout on my powerbook. Just installed the OS X port of Pcsx — so far everything runs reasonably well. It won’t let you listen to the music from the cd-tracks while you play, but iTunes will help you with that. Rumour has it you can plug in your controller pad if you want more control than your little arrow keys acn give you.
I’m not into gaming at all, so I can’t tell you how different games work: I don’t have them and I don’t play games… Pretty damn cool anyway, though…