I've just upgraded to 1.3.10 from 1.3.9sr1 and everything is going fairly smoothly. However, when I create a new story and then come back to edit it, I get this error message:
The ID you chose for this story is already in use. Please use another ID.
I copied the PROFESSIONAL subfolders (admin et. al) and overwrote all the apv_aeon subfolders (since I hadn't altered anything in them) and that did the trick.