A new report from Nielsen found that the amount of time spent on social-networking and blogging sites tripled since last year, ReadWriteWeb reported.

The study found that those sites represented 17% of total time spent online in August, up 6% from August 2008.

Nielsen added that ad spending on social networks and blogs more than doubled, to $108 million in August 2009 from $49 million in the prior-year month. The company analyzed 13 industries and only three (entertainment, financial services and hardware/electronics) chose MySpace, while the other 10 went with Facebook, according to ReadWriteWeb.