I've heard various ideas such as limiting it only after mods have expended their points (this will require implementing a cooldown to prevent a user from getting points again too soon). I want to hear your feedback, and I'll roll together something for the next major update of the site. Leave your comments
I also like the idea of "levelling up" as karma is accrued. Perhaps certain amounts of karma could endow a user with a "title", like some other forums do, which could be displayed along with their UID in comments, so we could see at a glance where they are in the SN pecking order.
I'll second this. Say, for example, a user posts a lot in Science stories, gets several +5's. Give them a "science initiate" title. More +5's (particularly weighted towards "informative"?), "science guru". Stuff like that.
I think it would be an alternative way of having some kind of authoritative voices involved in discussion, kind of like having accredited experts (i.e. have a degree) which could be valuable once we get enough posts that the threads need moderating to follow easily.