Go to the global comments section under your account page. This page gives you the option of moderating all hubs, choosing to moderate or not moderate on each hub-useful for those who sometimes but not always write on controversial subjects-or not have any hubs moderated. You still have to approve them eventually so that the system doesn't think it is spam. But comments will show up on un-moderated hubs immediately. Denying them will hide them, but they will already have been read. That's why I put mine on moderated when I started getting spam. I still have to read spam, but no one else will on my hubs.