What do you mean by direct voting, and what are the implicit signals to "rate" posts? It sounds very interesting, and I would like to hear more. I am going to be creating a rating system soon, and any suggestions to prevent abuse or to accurately increase quality would be appreciated.
direct voting: having an up and down arrow, or a "digg" button. one of my favorite old community sites (half-empty.org) had a buttons for + = -. This was before the term blog even existed, and that site suffered the same problems, and had endless meta discussions about it.
I wish there were a way to send someone a private message, cause I'd give you more specific details. Anyway, the site I built, which gets about 10k uniques a day and has around 200 active users, uses the ratings of posts to sort the homepage and the tag pages. It uses a few different signals like the number of distinct commentors, click throughs, and the reputation of the poster (this is mainly to break ties). It has a decay so that new posts come up, and it also has some safeguards for abuse. For example, users with no or very low reputation don't count in the distinct commentors number so that it can't be spammed, and there are similar safe guards for the click throughs.
Building community sites has been a hobby of mine for years, and I have a bajillion ideas on the subject. Right now I'm working on some bayesian filters for collapsing insulting comments, porn, etc. Fun stuff :)
