Logging out of the main alpha site currently doesn't automatically log you out of the forum.
The navigation bar in the forum is not as well integrated with the webapp as it will eventually be.
Clicking on your username in the navbar of non-forum pages may result in an internal server error message.
"Add a profile picture" link on forum profile fails with "Whoops! There was an error." (Note: The most likely plan for forum avatars is to have it automatically show your ingame avatar, but we don't yet have the necessary infrastructure in place for generating sprites/images for player avatars.)