I am not sure if this has been discussed already, but today I went to rearrange the order of my mail inboxes on the mail application. I clicked EDIT in the top right corner as you did with iOS 6, but I discovered that you could add ANY email box to the front page of the mail application including FLAGGED, UNREAD, SENT, etc. It is great to be able to click one place and see just the unread messages between all my mailboxes! I have been waiting for this on the iPhone.