The Rdio Web Service Ruby SDK by Rdio allows API interaction to implement audio and music streaming. Examples show how to authorize user credentials and create playlists from artists. Rdio has been recently acquired by Pandora. For integration updates, follow @Rdio on Twitter.
iLike, Facebook's favorite music service, has officially launched their new API. TechCrunch reports that iLike is partnering with Google, TypePad, Flixster, Connected Weddings, and others, in the launch. The music itself is provided by Rhapsody.