The Echo Nest, a music data company that specializes in recommendations, playlists APIs, and artist/fan understanding, has been acquired by Spotify. From their blog post:

Spotify shares the intense care for the music experience that was the founding principle of our company, and it’s clearly winning the hearts and minds of music fans around the globe. Our dedicated team of engineers, scientists, music curators, business, and product people are utterly electrified with the potential of bringing our world-leading music data, discovery, and audience understanding technology directly to the biggest music streaming audience out there.

The Echo Nest is the artificial intelligence that powers several features of over 400 modern music streaming and online radio services, including Rdio, iHeartRadio, and SiriusXM. The Echo Nest provides features that are often essential to some of these services, such as audio recognition and fingerprinting, music discovery based on listener tastes and patterns, metadata cleanup and artist bio updates, and playlist personalization.

According to The Echo Nest, the API that allows apps to use their features will remain available:

You’re about to see some great stuff from the new Echo Nest-enabled Spotify, and we’re excited to hear what you think. We’re all staying in town, our API stays up, and every single person at our company will continue to focus on building the future of music. Talk to you soon; we’ve got some work to do.