I think there are many things that are good in moderation for a forum, such as cuss words, repeated topics (one might be old so they made a new one) um, let's see, banned accounts is one of them for me personally but I was never one to ban unless it really needed it (it is the internet overall), that's all I can come up with.
Moderation is good in moderation but bad in excess.
Seriously though. A nice mod team who take care of the odd troublemaker and ban spammers, that's good. A ridiculously over the top admin or mod team that bans people for grammar mistakes and acts like they're god... that's gonna kill a forum very quickly.