(Applies to: FusionBB version 2.0 and newer)
You can define that at a certain post count, something happens: users can be added to a group, removed from a group, or both. (If they need to get added to or removed from multiple groups, you have the ability to create multiple entries for the post count at which that happens.)
This is located in the following section of the AdminCP:
Admin >> Groups >> Group Advancement
As a user makes posts, their post count is checked by the software. If the post count matches the list, then the action is performed.
- This is an excellent way, for example, to setup the users group that everyone is in to be more restrictive. When they reach a certain number of posts, they can get added to a group which grants them more rights (or less restrictive posting rules, flood control etc...)
You can also use this feature to control spammers. If you create a probationary group which allows for no markup, longer times between posts and other rules to limit spamming, you can limit the impact the spammers have. Once a new user has proved themselves they would automatically graduate to the members group (with more rights).
(Thanks to FBB Developers Josh Pettit, Dave Lozier, and FBB member Greg of FusionBB for this info!)