Grooveshark has opened up  a trove of user data to the world for free, via an in-depth analytics service called Beluga . The data Grooveshark has collected is anonymized and comes from surveys that users have responded to in exchange for points on the music network. User information spans a whole gamut, from the cell phones they use, to their annual income, to the kinds of nail paint they prefer. The data also includes age and sex demographics information, and of course, the time, frequency and device used for music listening--all searchable by artist. Grooveshark hopes the free data and analytics will help artists understand their audiences better (though, as TheNextWeb  rightly points out, the pool is skewed towards a survey-answering, Grooveshark-using, BlackBerry-weilding demographic) and even perhaps snag advertising partners on the music network--a plus for Grooveshark and a bonus for the artists on it.
To keep up with news as it happens, check in on our main Fast Feed page .