Hi Guoda,
I understand the need for the copy/move between indexes, Do you think that an export import would be good for this?, something like exporting to an XML based format and the ability to import from it ? this way you will also be able to backup your tagging work in a more open format.
I was thinking of changing the File->open to something like 'manage indexes' and put something like a favorites list in there.
Asaf.
BTW, thanks for the support this what makes this so fun to do,