Comment 2 for bug 715635

Jamendo and Magnatune in Rhythmbox are the way to go, but that's for free music.
eMusic has an API: http://developer.emusic.com/ It doesn't seem to allow purchase, though.
7digital also has an API: http://developer.7digital.net/ But it seems to be dependent on a web browser anyway, so we'd better simply embed Ubuntu One Music Store which is just a wrapper to 7digital.