The header for this page says "You're looking at Less Wrong's discussion board. This includes all posts, including those that haven't been promoted to the front page yet.". It's inaccurate because Discussion doesn't include the posts which were started in Main.
If it's worth saying, but not worth its own post (even in Discussion), then it goes here.
Notes for future OT posters:
1. Please add the 'open_thread' tag.
2. Check if there is an active Open Thread before posting a new one. (Immediately before; refresh the list-of-threads page before posting.)
3. Open Threads should be posted in Discussion, and not Main.
4. Open Threads should start on Monday, and end on Sunday.