1) I'm working on the replace/add/no-action option right now, actually. This didn't come up until I implemented the 'run rules now' feature, since new files wouldn't have existing tags. And I like the idea of being able to undo, but I don't think I follow how the new attribute would allow it. Can you expand on that?
2) When new files are tagged, yes (though I haven't specifically tested mp3s). The db is updated just before the sync occurs, so id3 files are written out as UpdateMedia continues. The 'run rules now' is a separate executable though, and the id3s aren't synced until the next UpdateMedia run. I didn't think that was a big deal, but we could consider adding in a call to fire off UpdateMedia at the end if necessary.
3) I didn't know what that attribute was for until you asked the question, but yes the backend supports it. It would be a rule like:
[/home/public/data/pictures/myscreensaverpics]4) Both. First, an update to UpdateMedia for new files, which updates the new File row before the id3 is synced. Second, the 'run rules now' is a standalone that uses the same library to load and execute rules against only files that are already in the db. Note that when I say 'new file', I'm referring to new according to UpdateMedia. Files that are moved to the directory and recovered by UpdateMedia will have their paths updated in the database, but it will not trigger the auto-tagging. The standalone would need to be used in this case.
ShortAttribute, 30, *, true
5) Shaky, but yeah that's probably my next step. I was thinking I would extend the existing media sync screen, but it's starting to look like the rule definition will be different enough from the attribute creation that it will warrant a separate section or screen.
No problem, good questions and you are giving me some additional ideas for testing. BTW, do you think the approval process is worthwhile? I'm seeing it as something you use as you work through and test your auto-tagging rules, and eventually disable when things are running smoothly. It's probably a significant extra bit of work though, so it's not worth it if it's just going to get in the way.