Say Andy, what happened to hip hop anyway? I think a big part of the appeal of hip hop was its social nature. Not social as in getting together with your buddies to smoke weed, but social as in social conscience, concern about the community etc.
Whereas rap is basically celebrating your own wealth and stagnation.
What happened?
Simply, it just got popular. First thing that happened was what it was about. It used to be about community, where they lived, the problems in society, but then that stopped. Another reason is the beats changed, the simpler beats that were not as catchy mean there had to be really good lyrics on top of them. Later, the beats became more electric and popular, so people could dance to them, it didn't matter what they were singing about.
One of the last reasons is popularity, the more popular, the less work one has to do to get out there and be famous. When it is underground, you have to struggle and work really hard, especially if it is all lyrical based. But alas, that was long ago.