CC licenses are not compatible with users' listening stats, because many
countries have special database laws. The
http://wiki.openstreetmap.org/wiki/Open_Database_License may be a good
alternative. However, users should have the option to set whether their
individual listening data may be commercially used. It could work like this:
When a user sets his/her listening data to non-commercial, stats are either
submitted anonymously to the overall database (which should be plain OpenDBL)
or not at all.