There have been a few awesome Web-only radio services to explode in popularity lately. Probably the two biggest are Last.fm and Pandora. But neither does a very good job of spreading their services “viraly” by allowing open aggregation of playlists and stations.
Last.fm’s facebook app focuses on showcasing your compatibility with friends’ musical tastes. And Pandora shows what your friends are listeneing to.
But what these services really need to offer is enabling users on other sites like Facebook, to get hooked on Web radio’s functionality, so they see value, and are motivated to participate. Seeing what my friends are listening to is cool — but not when it’s just a tacked-on Facebook app. So it’s really two things:
Social motivation of seeing what my friends like
Being able to find what I like IN-context, without leaving facebook
The one service that does this really well, is a simple “search-driven” playlist site called Project Playlist.