• November 15, 2007

Among top social networks, Linked-In was the fastest-growing over the last year, according to October ratings released Wednesday by Nielsen Online.

The site geared toward professional users drew 4.9 million visitors last month, up from 1.7 million a year ago.

Other fast-growing social networks included kiddie site Club Penguin, up 157% to 3.8 million users, and Facebook, more than doubling its audience to 19.5 million in the last year. MySpace remained the top social network with 58.8 million users, up 19% from 2006.

Blogger was the top blog-hosting service in October with 34 million users, followed by WordPress.com (11.4 million) and Six Apart (10.6 million.

--Mark Walsh