Profile Fields (username, avatar, location, user title, sidebar) and Signatures are not to be used to make political or religious statements. Sponsors are permitted to have a signature of up to 5 lines, 1 image and may use up to size 4 font. Video code may not be included in any signature. As stated at the top, all other rules of conduct apply to these fields. Do not use them to flame, troll, insult, mock, display offensive content, or promote anything illegal. URL's may not be displayed anywhere but your signature and on the homepage field in your profile. Use of other profile fields is considered advertising.
This includes all the Paul Holmgren avatars with "ASS" stamped on his forehead. This is something that's been brought up before. You're all being given a chance to change them over the next day or so.