Web music: On the threshold of a stream
For all the talk about satellite radio, the most vibrant frontier in radio may be the Web. Many traditional AM and FM stations have begun streaming on the Internet, along with hundreds of smaller online-only operators. Even subscription download services like Napster, Rhapsody and MTV's Urge have pre-programmed radio for users who are not in the mood to hunt for tracks.
Currently, the most compelling online radio is interactive. Services like Pandora, Last.fm and Slacker evaluate your musical tastes, then serve up a continuous stream of programming to match. They mix familiar songs with new material you might like. They all do it by harnessing the technological forces of social networking, data mining and music analysis, though each uses a slightly different technique.
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