I have noticed, as well as a few people have messaged me about it, abuse of the rep system. It is just a simple forum feature for people to have a little reaction to a singular post based on the content of that post, be it positive if it is a beneficial post or if you really like the content, or negative if it is detrimental or you really don't like the content. Not something to have a personal vendetta against another user to down vote every post of theirs.
Personally, I feel it is ok to have both the positive and negative if the system is not going to abused. But, if it is going to continue to be abused, I will turn off the negative option and we can move to being like other forums where it has to be a safe place and we can't have any critical thinking.