I'm not a big fan of hip hop or rap, but a lot of my friends are. I don't know if I would call those lyrics genius, although it's unfair to make such a blanket statement about urban music that's retarded or without talent.
Artists like Common who say things like,
"We got arms but won't reach for the skies
Waiting for the Lord to rise
I look into my daughter's eyes
And realize that I'm gonna learn through her
The Messiah, might even return through her
If I'm gonna do it, I gotta change the world through her"
Are a good example of intelligent, thought-provoking lyrics laid over what could easily be called music. The song is driven by a very catchy stand up bass line. You just have to wade through a lot of young male posturing which is prominent in all "youthful" genres - including my favorite - which is heavy metal. You have groups like Iron Maiden who write epic progressive songs with lyrics based from Robert A. Heinlein novels. On the other hand you have a lot of what get's played on the radio which amounts to Cro-magnons bellowing over distorted guitars about shallow boy-girl relationships.