rap has gone the usual cycle that all popular music goes through. a new genre starts out and its the shit. then money gets its grip on things and generic talentless people come to the fore front. people then get tired of it and move on. for example.....

80's
van halen, quiet riot, ac/dc>>>>>>>>poison, cinderella, whitesnake etc.

90's
nirvana, pearl jam, alice in chains>>>>>>>nickelback, and a bunch of other generic popish grunge bands that i forgot about because they suck etc.

2000's
run dmc, public enemy, nwa>>>>>>>>>>>>mike jones, 50 cent, Big Joe etc.

footnote: rap was never really all that good but i will admit it has gotten much worse