Planetside from all the time iv'e been on it (day 1, then left for about a year, playing again now) I havn't found an aimbot hack for it. It has had a few exploitable bugs (ps was originaly fully client sided, this allowed users to simulate a temporary linkdeath, kill the people who are now not moving on their screen, then let the game catch up and boom, the other guys die) that are fixed (still alot of client side, but makes all attempts to freeze your game once your lag is above 1.5 seconds or so). there is still the issue that dell laptop users with SpeedStep tech can "accelerate" their game, thus their run speed. A bug that can't really be "stopped", how ever someone can report the user, logs can then be checked (user does not need to be caught in the act by a GM), and the user will be banned.
I like PS, its not the best, but no body else is doing large team based first person shooters!