Nielsen; The amount of time spent surfing social networking and blogging sites had tripled since last year (US)

"In August 2009, 17 percent of all time spent on the Internet was at social networking sites, up from 6 percent in August 2008.

Among those taking note of this trend: advertisers.  Estimated online advertising spending on the top social network and blogging sites increased 119 percent, from approximately $49 million in August 2008 to approximately $108 million in August 2009 – all despite a recession. Share of estimated spend on these sites has doubled, from 7 percent of online ad spend in 2008 to 15 percent in 2009."