Compatible with OS X, Windows, Linux and Android devices, Google Music is able to manage the music we want to climb the Google cloud to hear from wherever we want. We have our music library on a hard drive to take it into the cloud, we can upload up to 20,000 songs completely free. Google Music sells ... and also offers exclusive In the Google Music Store find, finally, interviews and extras bands present. Let your friends hear the same thing you once ... how to jailbreak iphone

The main novelty is the long-anticipated opening of the iTunes Store from Google itself. Comes integrated with Android Market and sell albums and songs in MP3 format at 320 kbps quality.
It will offer free and exclusive songs. Among those announced today, giving the concert in Madrid to present his latest Coldplay caramelito, several unpublished direct Pearl Jam concerts and also never heard of the Rolling Stones.

Much had been said integration with Google+ and this comes in the form peculiar. Each user can send music purchased on Google Music Store to your circles on Google+ and there your friends can hear each song in full once. No, this is not Spotify + Facebook, but it's something.
Google has negotiated with three of the four major labels: Universal, EMI and Sony Music (of course Warner) for the content of your store. And also has the support of the indies, to a catalog of over 13 million songs and a thousand labels. Google Music Artists Hub: The Bandcamp of Google