If you don't mind my saying so, most of the moderation suggestions I've seen here are subjective and subjectivity will almost inevitably lead to squabbling and resentment. I think there need to be moderators to perform the dull, boring, back-office tasks of confirming that a message conforms to previously defined standards and letting it through. Or rejecting it for one or more of those previously defined standards (and maybe emailing back a non-personal standard script to the author explaining the rejection?)
I subscribe to a moderated USENET newsgroup on the subject of UK law. There's no moderation on content but a post may be rejected for a number of reasons including being abusive to other posters, being potentially libellous or likely to be in contempt of court. So a patently wrong message such as
"Murder is not a criminal offence" would still be allowed but
"Murder is a criminal offence, you stupid dork" or
"XYZ Corporation murders babies" or
"We must lobby the jurors of the ABC murder trial and make sure they vote 'guilty'" would not.
Regular posters get on well with each other and newcomers don't feel threatened and some interesting conversations - both deep and frivolous - take place.
If you are interested in the way this group works, take a look at
http://www.usenet.or....moderated.html and click through to any of the links
If you want to see moderation at work in real time (subject to the time zone and the moderators actually being on line) try watching
http://www.chiark.gr...~webstump/l.ulm