Just my 2 cents worth:

I would like the ability to double-vote a really significant post. That includes up and down.

I don't think there should be an additional bonus to the voter for double-voting. If someone wants to cry that they don't get as much XP as they would if they used the two votes separately... screw them. This isn't an RPG.

I value my privacy! I don't want someone getting a message stating that I double-voted his post whether it was up or down. I don't want buddies or enemies and I definitely don't want obligations. Our posts should be judged based solely on the quality of the post.

For example, if a monk usually posts helpful and insightful messages, I might vote him up without replying to his posts. If the same monk posts just to flame a newbie I'll vote him down. I don't feel bad and he doesn't have the opportunity to think "WTF... this guy usually votes me up."

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-- GhodMode