Rap is full of songs that are all about getting drunk/high/whatever people are doing these days, getting paid and getting women and Eminem dares to be different (mostly). Though some may dislike his content, the man is a genius at wordplay and has a talent for imagery. His style is his alone.
Granted, he did first gain fame because of his race, but I believe he transcended that. He is one of the best rappers in the history of the genre.