There have been so many wonderful ideas over the years for sharing music on Facebook, it’s generally disappointing to see what actually gets launched. Basically, due to music licensing issues, there is still no good way to create and share playlists of full songs — the sorts of things you can do on sites like MySpace and imeem.

Latest example: iTunes 9. Today, Apple announced a new version of its ubiquitous music player, that includes ways to share tracks from iTunes to Facebook or Twitter. Both options are buried at the bottom of a drop-down tab in the iTunes store. With the Facebook integration, you don’t actually share a song, you just share the album art for the song and a link to the song within iTunes. The upside is that some fraction of the tens of millions of people who use iTunes will probably use this feature, leading to a little more music-information sharing. Previous rumors suggested that more advanced features might be coming to Facebook via iTunes, such as a way to share iTunes playlists into Facebook. Maybe we’ll see that in the future?

Third parties have tried offering streaming music over the years, from early applications to Project Playlist, and many have been shut down over licensing concerns. Facebook itself has also looked at how it could offer some sort of streaming music service, but that project seems to have stopped before anything could come of it. For the time being, music on Facebook is limited to third parties that let you share individual songs or music videos, or related things like finding nearby concerts. For Facebook’s nearly 300 million monthly active users, the experience is still underwhelming.