I have a Mac Pro, and all eight cores show up in Task Manager -> Performance. But only one, maximum two, shows any activity upon export.

Apple promised Win7 support within the end of 2009 - in which they have failed to do. I haven't bought Win7 yet for the Mac Pro and probably won't do that until I know for sure they have support for it.

However, when I use LightWave 3D on the Windows part, all the cores seem to do their work just fine.