Here's a suggestion
If this is truely to be a forum geared towards SS fans (meaning people who love "Sesame Street", and not just simply one person or muppet character who happens to star on it), you may want to make some sort of reference regarding this.
I have noticed, on this and other forums, that people who only focus on one character never seem to want to talk about anything else, and seem to get extreemly offended at nearly anything even remotely negative that happens to be said about the character. These people are usually the ones that provoke more flare ups and anger and hostility,in general, than any other type of person.
The same goes for people who don't like any certain person or character, and only plan on making statements that are cutting or belittling to that character. If people plan on only concentrating on a single individual and don't plan on talking about anything else, (either possitively or negatively) than you might suggest they join forums that are geared specifically toward that character alone.