Pandora has been a trailblazer in collaborative filtering and the ability to help music fans listen and discover music combed from their Music Genome Project. Fast Company has a great article this month to give a view behind the scene of Pandora including a video interview with their Founder, Tim Westergren. Here's the video:
What I like about the video is his acknowledgement that the secret isn't the matching algorithm that powers the music suggesting service, its the people who categorize the music. And the enormous effort that it takes. The video snippets of scores of people sitting at long tables ostensibly listening and categorizing music was a little sweat shop like...albeit one of many music lovers who are selectively screened for their musical knowledge and ability to discern musical genres.
This was doubt meant to be a favorable article for Pandora, it didn't acknowledge how Apple's iPhone and itunes saved Pandora by providing a scalable revenue stream to them. Pandora rounded the corner from good idea stage to personalization stalwart when Apple signed the deal to allow Pandora listeners to download songs heard for a cut of revenue from each download. The success of the iPhone pulled Pandora along for the ride to the good fortune of all of us.