Metrics for comment approval might include opening up a thread complete, or for folks with a karma threshold, or who have made posts in the past without being downvoted much. (The _Making Light_ site has some interesting ideas here).
You might include who voted on an article, and how. If someone's gonna moderate, they may as well be listed as having moderated (so they can get the credit or blame). Meta-moderation might be one of the things that killed Slashdot, though.