Several additional messages/points, including the parenting and hygiene stuff.
Ye olde "Don't worry, I'm [insert minority group]." It seems like it is not aimed at certain hypothetical people in da ghetto, but more at middle-class consumers. The creator laughing at the audience laughing at a distorted stereotype? Silly novelty, as the same piece created by a white person should stand on its own merits if it is well written. This video could have been much better, but as it is, I don't find it particularly amusing.
To my surprise I found the SNL 'Dick in a Box' video very funny. The humour appears to stem firstly from the absurd nature of the lyric contrasting with the musical style, good delivery, and nice touches.