Add filter on `wp_insert_post_parent` to make sure we always have a topic parent (forum).
Add functions for making posts "orphans".
Don't track reply forum as metadata.  That's just one too many levels of confusion.  It'll come back to bite me in the rear end later.
Remove older action on save post.
Some cleanup and inline docs.
Introduce setter functions for forum meta.
More cleanup and inline docs.
Add sticky and super action links on the edit topics screen. Fix bug with removing a sticky topic.
Edit posts screen style adjustments.
Add setter functions for topic metadata. Fix issues found in the process.
Introduce the `mb_set_topic_position()` function.
Revamp some of the query filters.
Add the `mb_is_forum_category()` conditional function.
Redo some of the query stuff to simplify things a bit. Some of this will make for extra code in themes, but it will simplify matters.
Beef up `mb_get_reply_id()`.  Add `mb_is_single_reply()` and `mb_is_reply_archive()`.
Random cleanup.
Beefing up a lot of the user functionality.
Early, early look at the template system. Dipping my toe into the water with a topic form template.