Apple just launched iTunes Preview. They opened the pandora's box. Because of that, iTunes will be forced to offer "full preview" of all songs in a "near" future, a prediction I made a while ago. All Spotify has to do is a light enhancement allowing arguments on the command line to include a title, an author, an album. Deezer could do that too with its URIs. Who'll be the first one to write a Firefox add-on detecting iTunes link, parsing the remote HTML document and triggering direct and full audio of the song through Spotify/Deezer/whatever ?