Just ask regular players about the security of the MMORPG's that they play.
Most are regular hack fests.
Ultima Online: Scripting in the number one player complaint, but EA doesn't give a rats ass, they never ban, despide their TOS saying otherwise. Other cheats include ways to make players drop items, and using bots to monitor certain parts of the game for the sole purpose of knowing exactly when to raid, and then there is all the speed hacking (EG movement hacks) that goes on.
Lineage II: I played for 6 months, and never met another player, just about 4000 different bots.
LOTRO: Besides the game missing something, it had its share of bots.
WoW: I get spammed with cheat site URL's every time I login, regardless of realm.
Of all the above WoW seems to have it the most under control, but that doesn't mean they don't have room to improve.
Cheating is so rampant in Ultima Online anymore, that the fricken game isn't worth logging into.