yeah the only ones can think of are World of Warcraft and Everquest Mac. Runescape of course can play on Mac. Not many others than that, so if you own a mac and want to game World of Warcraft is your best bet.
Planeshift works on macs :S (its REALLY BUGGY but the community is good and its gonna be good someday .... and will be free :P ) (and i like the mining, melting, stocking, heating, forging system :P )