thecoalman - 2:58 pm on May 30, 2010 (gmt 0)
The white/black listing is a good idea.
In addition to that you could set up an internal scoring system. The member would need to reach a threshold before their links would automatically be published without moderation. You could base this scoring system on a variety of things; posts, length of membership, score the links themselves where a posted link that gets rejected or approved during moderation will add or subtract from their score.
You keep the member in the dark what the threshold is and what their score is.