I've split this from the Future J2O thread.

Dermo: the grey dot means that 0 reputation was given.

The amount of reputation power you have depends on how long you've been a member, how many posts you've made, and how much reputation you have. There's also limits on how much reputation you can give per day and how often you can hit the same user (unless you're an admin... ).

Oh, and those who are notorious for their worthless posts cannot give out reputation