There's one word that gets my goat in WoW: "noob". With spellings as diverse as "nub", "n00b" and "nubcakes", dropping the N-bomb is seen by many players as a way to enhance their own social standing -- often with the opposite effect.
I'm tired of "noob" being the default insult -- of Trade, General, LFG and local channels filling up with the word time and again. Of being called a "nub" for reasons as diverse as refusing a duel, wanting to find a group and capturing the flag in WSG. Of course, sometimes we do behave in ways that deserve reprimand -- but can't anyone come up with a more original insult? Perhaps that should be the next Blizzard competition.