PiCaSSo: Geez, just go in your profile settings and enable avatars.
ViCiOUS: Yeah, it's looking that way. If somebody doesn't like you, they're probably going to give you negative karma regardless of the quality of your posts, and visa versa.
I think the ideal system would be post based: each person could make one vote per post, and if that post's overall rating was positive, it would add positive karma. If it was negative, it would add negative karma. I think that would still have just as much potential to be abused, though. If somebody didn't like you, they'd go through all your posts and give them negative points.
Looks like there's a pretty even split on the votes. I'm leaning toward removing it, but I'm curious how it would pan out in the long run.
blaa: I've been on forums with the reputation system and didn't care for it much. The people who posted the most got the highest reputation, period. Even if they were the most annoying/spammy posters around. Meanwhile, the people who only posted occasionally, but had quality posts only had a small amount of reputation.