After the hell that was the 90's, most fans who are probably obnoxious, i.e. students, hadn't been there before. That is where most of the complaints have been lodged. But it has gotten much better. For example, in 2003 during the Auburn game, a security guard i know had to throw out 23 people. In 2005, after Katrina, during the Auburn game he didn't have to throw anyone out.
Skip Bertman has also laid down the law a year or so ago about the fan's behavior.