He's always saying he likes Kid Cudi too. And he's said loads of times he likes Paper Trail by T.I. (which, I agree, is a fantatsic album!

).
To be honest, he probably listens to similar things that the rest of us here do. Like mainly American hip hop music, and a combination of mainstream and not mainstream.
In terms of other genres, he hopefully hates country music, and he's been quite clear that he's not overly fond of most pop music. I doubt he likes dance and electronica either ("Nobody listens to technooooo"

). I heard he likes some rock music though. Don't know what he thinks about RnB...