Sparkly – I’m sure that there are things that have gotten past them. It’s hard to monitor %100, especially since hilchos lashon hara can be very complicated, and on such a site, where the purpose is discussing issues in the Frum world, it can be very difficult to differentiate b/w LH and non-LH.
Bottom line, everyone has to take achrayus and not leave things up to the moderators.