Mmm, if you look at the site it's really not that surprising it didn't take off.
Landing on that site and seeing the big 'Create Sale' button is pretty confusing. I don't think 'oh this is a site for musicians to sell their music directly to fans'. It also claims I can use 'social sales' but is that a meaningful term? I've never heard it before and it sounds pretty buzzwordy.
edit: Just watched the video on the front page and I can easily believe that only 1 out of 1700 people thought it was worth bothering with.
The execution just seems awful.