i have tried Illustrator once, a while ago on a mac at my church, but i really just opened it, and looked around, didnt do any actuall work on it...
i know the basis of raster vs vector... color changing wise and stuff... but other than that i havnt studied it - i guess thats the best way to put it...

oh and the fact that it sucks when you try and blow stuff up, or well re-size things... lol...