Currently there is no content editing lock. This can result in issues when 2 editors are working on the same content.
In example editor 1 has saved some changes, while editor 2 has the same (old) content already opened. Editor 2 saves his changes after editor 1, and the changes from editor 1 are lost.
Realtime editing with multiple editors would of course be the future, but in the meantime I would suggest a lock on the content, similar like in the WordPress CMS.