I've tried the app a couple of time in the last few weeks. I've been a bit disappointed by the music recommendation and what was suggested to me. I.e. I don't care about "What everyone is listening" as I don't like it. I have no friend on it. I understand that with friends and probably lots of like/dislike of music, it'll be easy to narrow down my taste. But, I think you need to find a way to get the user started with something he likes; and make it easy to skip music he doesn't like.