On-demand music service Spotify, which is currently available only in Europe, has been broadly praised by users (including me) for its large selection of music and exceptional responsiveness. Today, Spotify added two new levels of service: Open and Unlimited. The Open tier is more notable because, once again, it opens the service to users without an invitation.
The new levels are the latest step in Spotify's ongoing experiment to broaden its audience without compromising performance. When it launched in 2008, Spotify was free and offered unlimited streams to a PC, but an invitation was required. In February 2009, it … Read more