According to their website, the new application, Echo:

More than just a radio player

Leverages the best of the Internet to bring you the music you want to hear.

Just type in your favorite artist or musical genre and echo will do the rest. echo even suggests similar artists based on what you’re listening to, helping you to discover new music or remember forgotten favorites. Not sure what to listen to? No worries, hit the stars to display the top artists in your country.

Once you’ve fired up a station, sit back and let echo serve up a never-ending stream of songs. We’ve even included a visualization mode that displays artist art based on what you are currently listening to.

Echo has a beautiful User Interface.  On startup, you’re presented with a tagcloud of popular artists.  I’m not sure from where they’re getting they’re songs, but they seem to have a pretty deep catalogue and robust cross-referenced database. 

When I plugged DJ Shadow in to their “Start a Radio Station” field, not only did a station start playing good music that I hadn’t heard before, but presented me with “similar” suggestions, including “turntablism,” which is really more what I was in the mood for.

At the top, Echo provides navigation to surface and save favorites, see your recent stations, and return to the tagcloud of popular items, which comes up as a nice overlay.

I’ve found some problems with the stream dropping out, but I’ve just started using the app, so I’m still optimistic it was just a glitch.

I’ve had the opportunity to work with thirteen23 with projects they’ve done for the MIX conferences, and are always blown away by their work.  Be sure to check out their site,which has an *awsome* video/infographic/bumper on their homepage, and the other projects they’ve worked on.