A cursory glance of the highest karma users demonstrates that it's mostly used for political reasons.
Would you please elaborate on that? I'm somewhat new, but I don't see it that way at all.
Edit: Also, what do you mean by political? Upvoting because you agree with the authors views on, say, cryonics, and not the way in which he reached those views? I've rarely seen something that would traditionally be described as political discussed on here.
Edit again: The only example I can think of is this.
My experience with karma-based community systems in the past leads me to believe frequently people upvote things on the basis of who wrote them. There does exist a kibitzer, but 1) one loses valuable information in the process and 2) the people swayed by political values like this are the not very likely to use it.
I suppose this post is evidence that the opposite direction is true as well.
Edit: I suppose "tribalistic" is a word with closer connotations than "political."
Aside: Every time someone says "would you elaborate," I think of Derrida.
People who go back and downvote every post or comment a Less Wrong user has ever made, please, stop doing that. It's a clever way to pull information cascades in your direction but it is clearly an abuse of the content filtering system. It's also highly dishonorable. If you truly must use such tactics then downvoting a few of your enemy's top level posts is much less evil; your enemy loses the karma and takes the hint without your severely biasing the public perception of Less Wrong's discourse.
(I just lost over 200 karma in a few minutes and that'll probably continue for awhile. This happens to me every few weeks. Edit: I mean it's been happening every few weeks for a few months for a total of only three or four. Between 400 and 700 karma lost total I think? I don't mean to overstate the problem.)