Invite your Friends to Google Music (U.S. Only)
If you have been wanting to try out the new music streaming service provided by Google, now is your chance. Google has now opened up invitations a bit so that additional users can experience the music service. Unfortunately there are a few downsides to this in that it’s limited to U.S. users only and that you have a select number of invites to share with others. Some, like me, don’t even have an option to share invitations. If you have access to Google Music and wanna share the love, log in and invite some friends!
Source: Android Police