None that I know of, maybe Rukas will have a better answer for that.
The only benefit I know of is the reputation itself, just that. It should give us an idea of who makes the good posts here and who doesn't (if the system is used in the right way).
Like KAMIKAZI said, you all need to cooperate if you want the quality of the posts to go up.
Lets say somebody posts a link to a tight song, instead of leaving 'thanks', why don't you rep the person? Silleone, lets say somebody 'schools' Jason G in a thread with a respectful & intelligent reply- rep that person. But try not to go around and rep people for 'owning' somebody because senseless 'owning' is the kind of stuff we're trying to get rid of. You know what I mean?