I want the play counts for songs in my Rhythmbox library to be the same as the play counts in my Banshee library (and vice versa). How can I do this?
Looking deeply into the problem for you, I have found no existing solution. Rhythmbox has a plugin to sync play counts and playlists to google music service, but banshee does not.
Looking thus further into the code, I can see that a python plugin for Rhythembox to save and load all the play counts, maybe in the file, maybe in ubuntu one or some other location. Then a program which manually opens the sqlite3 database of banshee to sync the data... such a set of tools could be written but do not currently exist.
Programmer Links for anyone wanting to attempt this:
If you are not able to build this yourself, it is possible to find a kindly soul or hire a programmer to build such things on your behalf. don't forget to publish the results so everyone can enjoy it and put a link in this question.