An update has been released for Outlook 2013 and can be downloaded and installed manually, but is also being offered via Microsoft Update.
Update KB2896300 for Outlook 2013
This is a non-security update which has been released without a change log. However, it also contains the fixes of the Out-of-Bind update KB2825632 to solve the Empty Folder Pane issue.
If you have Microsoft Update configured to also update other Microsoft applications, then this update will also also be offered via Microsoft Update or has already been updated automatically for you.