I've been using it since it came out... well, not All Access, because I've only been able to sign up for it yesterday (I'm in Canada), but I've been streaming my own music through Google Music's cloud service, mostly while driving in my car to and from work, and it's only used 1.47gb so far this month... Of course, it's considerable and you need to take it into acount, but really, what else are you going to do with your cellphone's internet when you're away from wifi? I have 6gb and I'm pretty condifent I'll never bust it since there is wifi everywhere... Plus, whatever playlists/albums you listen to the most, just pin them to your device. And allow for automatic caching over wifi.