At least I figured out what ambient occlusion was. Actually, I didn't. All I know is to turn it on whenever I want the renders to look better. In my mind it's the 'thingy-that-makes-stuff-look-real' button. :-)
I've been trying to make some sense out of Maya, too...but it's totally confusing. Too many key commands...and none of them do what you would expect them to.
Non-intuitive interface.
Grrrrrrr...
