Well The Boondocks basically is a racial comic, with a lot of the strip topics focused on the older brother (one with big hair) commenting on the silly stuff black people in entertainment business do and how they hold themselves down, and what he perceives as the reality of life. He's very pessimistic, thus his comment on not believing there'd ever be a black president
The Bauer thing was just commenting on the end of the season.
But yeah, if you don't know the comic, I could see it not being all that funny.
But since '24' has such a cult following, I figured I'd post it anyways.
Edit: Here's an article on the creator of The Boondocks, to explain the comics' mindset.
here