The Gamer-Island v4.0 beta is now under way. Sign up on the forum!
This issue has cropped up again. The query powering the forum index needs to re-written to stop forum categories being listed multiple times when certain conditions relating to the most recent post are met.
Turns out this was just a little bug in the big forum update, due to the changes to bumping. This is now resolved :)
This issue has resurfaced, working on a fix now.