Some time ago, we started getting hammered in the comments by Asian porn spammers, meat salesmen, and other reprobates. Because we noticed they tended to post a day or more after a post went live, we implemented a feature that would let us screen all comments that appeared a day or more after the post went live.
Since then, we've noticed a real drop-off in comments. I think one of two things is happening. Either the moderation feature is a disincentive to commenters, or comments are getting lost. Either way, this is not a good thing.
So here's my question. If we go back to unmoderated comments and add a rule against all advertisements, will that work better? Got any other ideas? Our comment zone is too important to us to see it harmed by bad policies. We want to encourage lively debate here.