Think of it as the old non frames version of the og before they switched to discourse. It's basically the same interface.
Here are some tips
When you upload (or attach) a pic, click the FULL IMAGE button before clicking POST REPLY. That will fully embed the pic in your post, instead of just a thumbnail of the pic.
themmacommunity.com
Also it doesn't automatically have you watch a thread you post in or create, there is a button at the top and bottom of the thread or Go through your user settings, you can enable it so it does it automatically when you post. Under settings, preferences, content options.
You'll get a notification with the bell at the top when threads have been updated.