When Spotify, the digital music company of the moment, announced this week an exclusive deal with Led Zeppelin and free access on mobile devices, it also reported impressive numbers. Its listeners have streamed 4.5 billion hours of music this year, and it has paid more than $1 billion in music royalties since its founding.But Spotify, a private company, omitted the results that music executives, competitors and investors care about most: how many people use the service and how many pay for it.
http://www.nytimes.com/2013/12/13/business/media/a-stream-of-music-not-revenue.html