these guys arent even in the same league to compare. Jay-z is what michael jordan is to basketball. no joke. yes tupac and biggie came before him and yes they were very good, but jay-z brought it to a new level. sure he's lyrically crappy now, but he's still a commercail success. he's so big it doesn't really matter. you can't deny it. but he knows it. he even says if he could be good lyrically, he would want to be talib kweli. all of new york and foreigners love him.
kanye isn't bad. he too sucks now tho. after late registration, his new stuff is pretty different. he still samples, but lyrically, its not good either. it is nice to see him try new things. he was great till about 2005. but he too doesnt have anything to prove now. he's also a commercail success.
both are awesome in their own ways, but you can't compare michael jordan to kobe. im not saying kanye is kobe, but i can't think of anyone else who good at bball.
in any case lebron>nba (and maybe life)