As with other ads, the difference between ads that hurt the UX and ads that help it is relevancy. I certainly wouldn't mind hearing sponsored songs that Earbits

As with other ads, the difference between ads that hurt the UX and ads that help it is relevancy. I certainly wouldn't mind hearing sponsored songs that Earbits can algorithmically determine I am likely to like based on my tastes and use of the service. A well-targeted system would also make it more viable for small artists, who could target small niches of customers that had a higher probability of converting to sales of merchandise, concert tickets, etc. This is what happened with AdWords. One might have expected AdWords to be a mechanism for large content sites with money to spend advertising to get a lot more traffic, but as it turned out AdWords was a boon for niche but profitable businesses.