I am kind of more expecting some improved compatibility for osX and a better integration for the mental ray. Most features are only available to experts in this area that have programming skills.

Maya 2008 is still running smoothly on 10.5.3 but the improved graphics driver does seem to mess it all up. Before the update i had to occasionally reboot maya because items in the menu bar didn't want to work anymore. Now these problems happen more often and the openGL viewports seem to get stressed out when many polygons are displayed. I run it on a octo 2.8 Xeon with a 8800GT.

Don't know if it also is just me, but when are they gonna make the nucleus multi-threaded? Doing a nCloth sim is so slow cause it only uses 1/8th of my system. This nucleus could be a sweet system because of the complex setups it can handle.
Or does it work on multi-cpu's for you guys ?

Who knows what 10.6 will bring if they will make non-multithreaded operation available over multi-cpu's. Maybe autodesk needs to put a little effort into support and maintenance for os-updates.