The number of people subscribing to legal music streaming services rose by 65% in 2011

"The number of consumers subscribing to legal music streaming services globally increased by nearly 65 per cent in 2011, according to new IFPI estimates.
Paying subscribers of streaming services hit 13.4 million in the year, according to the IFPI’s new Digital Music Report 2012 – up from 8.2 million in 2010.
Spotify reports it has 2.5 million paying subscribers worldwide, including over 400,000 in the US market since its launch there in July - and that it sees its expansion in the US as a springboard to international markets.
Ken Parks, chief content officer, says: “We were very focused on how Spotify, which had been a European service, would translate to the US. Now, having seen the acceptance in the biggest music market, it gives us a huge degree of confidence and optimism to expand elsewhere.”
Subscription streaming services have caught on "exceptionally well" in certain markets, says the report, particularly in Scandinavia.
In Sweden, says the report, subscription accounted for 84 per cent of digital revenues in the first 11 months of 2011, boosted by its national champion Spotify. Other markets saw sharp growth in subscription revenues, including France which saw an increase of more than 90 per cent in the first 11 months of 2011 (SNEP)."
Source:  Data from the IFPI's Digital Music Report 2012, reported by Music Week, 23rd January 2012
See the full report here