I primarily play on a PC - but I also play on my iBook some times at school.
My iBook is the second-most-recent generation. It's 1 Ghz, 768 megs RAM and the Radeon 9200 32 meg video.
It runs... and it's playable. I get about 10-15 FPS on average. It's not beautiful - but definitely playable... Just turn all the graphics settings down.
Also - if you're in a really busy area, such as the starting areas, the FPS rate will be down to 7-10. Don't worry - as soon as you get away from the crowd, it'll get better.
So yeah - in summary - not great, but definitely playable.
Also - aside from playing - I absolutely love my iBook. I bought it new 6 months ago, and have since fallen in love with using a Mac to do my work. Excellent OS, and it's immune 99% of the viruses out there so I don't have to worry when I'm surfing *questionable* sites. It's peppy - and the battery lasts 4-5 hours with normal use and 5-6 if you are careful. I love it!
Edited, Tue Nov 23 17:03:00 2004 by kingjord