Check out FeedForward: http://www.feed-forward.net we're doing a lot namely giving artists incentive to communicate better with our core application which gives artists more exposure when they give feedback for others' work. We also feature a commission free market --sell your work with nothing more than a PayPal account, and we'll NEVER take a cut. We've applied for YC several times, and have never heard back, accept for their generic rejection letter, but we've been at this for years, not months, and I am a musician, so I understand just how hard it is for others like me, and I'm going for community development over riches and fame... Thanks!