Here is a description of what The Echo Nest is doing as pulled from their website:

The Echo Nest: a company specialising in MIR research and applications.

Twitter has announced a pair of deals with music technology companies: The Echo Nest and Gracenote.

The Echo Nest cites social networks and location based services as two categories that may benefit, for example.

The Echo Nest is a music intelligence platform company that provides music services to developers and media companies.

The Echo Nest released 1 million of their songs for research purposes.

We use data provided by The Echo Nest to recommend similar artists.

It's called The Echo Nest, and they're doing what I've been dreaming about for a decade now.

The possibilities are endless, and this future is quickly approaching thanks to the work of companies like The Echo Nest.

These links are provided using data provided by The Echo Nest, which is a music intelligence platform.