Rockstar North has just launched a new patch (1.03) for GTA V that resolves the XP cash farming issues some players have been exploiting. The patch weighs in at 39MB on PS3 and 59MB on Xbox 360. The patch notes are yet to be revealed.
Unfortunately, according to some users, the player deletion problem still persists and Rockstar are working overtime on it.
This is how some people managed to get 4Mio. in no time!
GTA Online Make a LOT of Money as Fast as Possible on Violent Duct