emplode is having a lot of work done to it totally (Roger has been totally replacing the internal structure with something better so that all the things like searches, bulk tag updates (on the database, NOT on the ID3 tags) can be done).
One thing it does after it has downloaded the database is check that everything has the full complement of tags. If not, it offers to update your database automatically for you, and does so (adding bitrate, total time, etc tags to everything in your database that doesn't have them).
Hugo