Every user in the allowed groups can vote on any post they want, but not more than once. They can give it a positive or negative vote, which adds or subtracts a certain number of point's from the poster's overall reputation. Elite votes are one point, mods 2, admins 3.
The images next to posts display the overall reputation of the poster. Red means it's negative, green means positive, gray neutral. If a user has a "very positive" or "very negative" reputation, there will be multiple green or red images.
The groups allowed to vote will not change until I implement the new system, and that has yet to be planned. There are also no special prizes for high reputations.
One final topic: if you have some reputation votes given to you, a new table will appear in usercp.php that shows the type (pos/neg), post, time, and comment (optional) of the latest reputations.
I was hoping you'd figure this stuff out yourself so my fingers could be lazy...
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