This just in:
The Echo Nest, a music intelligence company providing enhanced music search, recommendation and interactivity technology to online music companies, launched its second hosted application, "Recommend," today.
Recommend is an application programming interface or "API" that helps music services personalize their websites to each visitor's unique music taste. Any music website — bloggers, social networks, Internet radio or retailers — can easily access the Recommend API to offer users better music discovery tools.
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The Echo Nest is offering a free version and "Recommend Unlimited" a fee-based, more feature-rich version of the API. To celebrate the release of Recommend, The Echo Nest is offering free "Unlimited" accounts to the first 100 small music websites who register for API access at http://the.echonest.com/.