I'll echo Kenny's comment... there are a number of people who are annoying that have to be dealt with... I don't know who the "most annoying" is, because I usually forget about these people, so it's usually just whoever is the troublemaker at the spur of the moment.
But having said that, even though we don't like people who break our rules and whatnot, it's not very nice to publicly post about specific people we don't like, so I'll keep my mouth shut.
But I guess I could talk categorically... the most annoying categories of annoying people are...
3/ Those who don't show respect for other members and what they have to say.
2/ People who repeatedly don't read the stickies or rules (first few offenses I'm patient with).
1/ Those who grossly grandstand. :Z