I'm setting up a site at the moment and am wondering how important it is to have a TOS. I'm inclined to omit it as unnecessary legalese that my users are probably not interested in anyway. But the latest Facebook has made me aware that in some cases this is something that people pay attention to.
Is a TOS necessary for every site?
Essential, unless you want to endure endless complaints about there being no rules, so how can they be banned because they didn't do anything wrong, because nothing's wrong because there are no rules.
Be blunt. Say that people are expected to behave well, and that if you think they aren't behaving well then they'll get one warning, then be thrown off.
Make it clear that you are a benevolent dictator.