Spotify has 10m subscribers, including nearly 650,000 paying subscribers

"[A]ccording to information shared this week by European sources, Spotify's premium subscriber total is now approaching 650,000.  The information comes from internal updates that Spotify issues to it content partners, which sources agreed to discuss with Digital Music News.    
One source pegged the number at "between 640,000 and 650,000," though the trajectory is obvious.  In mid-July, Spotify CEO Daniel Ek disclosed a premium total of 500,000, and topline registered users recently surpassed 10 million."
Source:  DigitalMusicNews, 21st October 2010