The karma system is a popularity contest as discussed in the various Hacker-News-is-going-down-the-drain discussions that have been popping up here a lot as of late. To any one who grew up with /. that's not a surprise.

In that respect I found kuro5hin quite interesting in, as it seperates out how many people voted the post/comment up or down. I wrote posts that had a lot of people agree (5 points) and a lot disagree (1 point) with very few in the middle ground, i.e. the audience was divided. I loved that. It means you are not sucking up to the majority yet not writing utter crap. Had you just computed the point average then that information would've gotten lost.