As found in Jorick's handy [url=http://www.roleplayerguild.com/topics/2572/posts/ooc]compilation thread[/url]: 

[quote=Mahz]I like this feature. It's an open-ended tool. Ideally, roleplays would be self-contained ecosystems like little pools of subforum recursion.

I haven't much pondered what that could actually look like, but [b]arbitrary tabs are a good start.[/b][/quote]

It is Mahz's intention to allow GMs to customize their RP's tabs as they see fit eventually.