As Eagleflip stated, you have to either do something REALLY bad once, or ignore repeated warnings to shape up in order to be banned.
Only the webmaster can ban someone.
The webmaster has asked all moderators to crack down on avatars that he deems "inappropriate".
I personally have no problem with Anna, but there are some others out there that are a little obcene. The webmaster himself has acted on quite a few, and only after he warned them to change it. I suspect this is what happened to FlyChicago.
The webmaster has said that he is asking posters to change their avatar voluntarily, and if they refuse, they will be banned until they do so.
Being banned for anything else involves being warned by a moderator for a violation of the forum rules, and then continuing to cause trouble. Then we would ask the webmaster to ban them. In my entire three years here as a moderator, I've only had to request about five people be banned, and all five were. These were individuals that were a chronic problem and blatantly refused to play nice after repeated warnings.
I rarely have to resort to that. If I have a problem with you, generally I will edit, delete, or close a post if necessary and send a PM explaining why, and that usually takes care of things. If this is met with resistance or future problems, then I will refer it to the webmaster.
Contrary to popular opinion (among some Delta pilots in particular), I have NEVER, EVER censored nor banned anyone for disagreeing with me on something I have said here. I understand that if I choose to voice my opinion on a topic, I am subject to debate just like anyone else.
I have acted on personal attacks, particularly those aimed at me. Personal attacks are my hot button issue.
The bottom line is that as long as you play nice and keep it clean, I don't have a problem with anything said here.
If4f,
Moderator