Spotify is used by 15-18% of the Swedish population

"The conversion numbers are getting better. "We're now in six countries, and have more than 320,000 paying subscribers," Ek relayed. Back of the envelope math? Paying subs are floating at around 4.6 percent, given a top-line estimate of 7 million users (also offered by Ek). Last month at the New Music Seminar in Los Angeles, Ek disclosed a paid subscriber number of 250,000.
Other stats from the chat? Spotify currently houses 100 million playlists, of which 30 million are albums. In Sweden, the app is used by 15-18 percent of the population, and the resulting swell is happening alongside album sales increases."
Source: Daniel Ek of Spotify, speaking at SXSW, reported by DigitalMusicNews, 17th March 2010