I PM'd admin about this a while back.
The football forum I moderate on has a simple "appreciate" button, which shows the names of the users who have "appreciated" the post.
That means only those who genuinely found the post useful or helpful will use the feature, as opposed to the idiots who troll here marking posts down to do nothing more than make themselves feel all self important and warm inside.
I've been marked down by people when asking a question regarding Launchpad having framerate issues in Lion when there's a lack of free RAM. I replied saying that I found it amusing because it was probably some sad nerd, sitting in his parents home, thinking he was defending the "honour" of Mac OS X having been using it for a fraction of the time I have.
It's a poor feature, and one I was told was being looked at being removed in favour of something along the lines of appreciations or likes.