Maya and Lightwave... (Score 1)

...are all I know on OSX. If you want to do character animation, Maya will top Lightwave and probably Electric Image or Maxon. But Maya's renderer is crap and buggy, and I don't know how good mental ray integration is yet, especially on OSX. Lightwave has a good renderer, but sucks for character animation. Also, not all the plugins you may need are available under OSX.