Not really for 3D (at least the one i use isnt) can anyone put me right on this?
Unfortunately no - there are 3 commerical systems (Torque, C4 and Unity) and a few free ones (Irrlicht - always behind the Windows version, usually by a couple of version, unless you try and compile everything yourself).
C4 has nice graphics, but its overly complicated (and the help files dont help much). The Intel Mac version treats the cursor up key differently to all other keys, and you have to start and edit the CLI before it will detect any type of keypress.
Torque - enough said about that.
Unity is a RAD system (the cheapest version only supports Boo and Javascript). If you want the full version, you'll need to pay £600. The layout of the screen is awful, and there doesn't seem to be an easy way of doing title screens etc etc (not that its any easier in C4).
There is supposed to be a new commerical 3D engine coming out this year, so that'll be interesting to look at.
So, unfortunately, at the moment, Mac's are really suitable for easy 3D game creation.
In the 6 months of having iMacs, my mother's had one kernal panic (most probably caused by Open Office).