@KevinH: How about adding the user name to the epub metadata section each time the dirty bit is set?
In Python you could easily get the user name via:
Code:
import getpass
print getpass.getuser()
and the plugin runner code knows the name of the plugin, which would be used instead of the user name.
This way
BetterRed could at least check who last updated an ePub.
Of course, this should be an optional feature.
Alternatively, you could have Sigil users define their user name or another custom metadata entry in the settings dialog, which will be added each time a book is saved.