from http://bugs.musicbrainz.org/ticket/1399

I'd like to have an option in Picard that, when activated, eases subscribing to all artists I own records from. This should probably mean "artists I saved albums" for, so I don't get subscribed to artists picked up from incorrectly tagged tracks from the net.

Best of all would be a persistent "encountered artists"/"subscribed artists" screen (accessible from a button on the toolbar) that makes subscribtion as easy as drag-and-drop from one side to the other.