One of the new features in our upcoming version 4 of Simple:Press is the ability to define a set of status codes for topics in a forum. The simplest way to think about these topic statuses is in terms of a support forum. If you think of each new topic as a support request, then you can apply statuses (such as new, ticket raised, closed, etc) to each topic as the issues are worked or resolved.
There are of course many other ways to use the topic statuses. Your imagination is the limit. You the User define the topic statuses via an admin panel. You can turn the topic status on site wide or forum by forum. Permissions control who can update a topic status. The topic status will appear in the forum page for each topic or at the top and bottom of the topic page. Forum users are also able to search for topics and posts with a specific topic status.
The best way to get a feel for an example implementation of topic statuses is to check out our Simple:Press Forum V4 Beta Support Forum.
Look for Beta 2 of Simple:Press Forum V4.0 to drop in the next day or two.