"Well-considered votes help the community by making our primary feedback system work, and should thus gain people XP." sez theorbtwo.

Amen! that is, amen, as long as "Well-considered" is the essential modifier.

If we come to suspect/find_evidence/believe that "ill-considered" votes are a problem, a meta-moderation system like that at /. might help... but, on the other hand, it doesn't seem to be solving theirs.