Quake 3 has been carbonized though I'm not sure what the state of UT is. Warcraft 3 is going to debute on OS X at the same time as PC. Tony Hawk 2 works for both 9 and X. There's been speculation on a starcraft carbonization. If you've never tried the carbon game called airburst, go out and download it. Theres also a push for tribes 2 on X. I think Alice might be corbonized, though i'm not sure.
I'm sure that the amount of available gamining titles will quickly increase soon. It is a superior gaming platform.
Dont take my word on all this, plus, other people problably know of some other titles.