(UPDATED) The Echo Nest has announced a new partnership with music subscription service Rhapsody. The deal will make it easier for developers to use The Echo Nest and the Rhapsody APIs together to build music applications. Last year, Spotify made apps a key part of its strategy, and now Rhapsody appears to be doing the same.
The partnership enables support for Rhapsody artist and track IDs to all of Echo Nest APIs via their Project Rosetta Stone. Developers can use Rhapsody artist and track IDs with any Echo Nest call, and each Echo Nest API method can be configured to return Rhapsody IDs.
Details on the Echo Nest / Rhapsody partners page.