You don't have to apologise for having terrible taste in music
I like him because he's a comedian first and foremost, but he still manages to write catchy music. I love his whole shtick where he acts like a hardcore gangster rapper but raps about boring everyday normal stuff. Pretty much taking the piss out of the whole rap culture of ego and bragging.
He does have a strange obsession with masturbation though, which gets a little old, but he could just be playing to his audience, being an 'internet celebrity' and all.
Fair - I really enjoy Flight of the Conchords running a similar schtick.