Social network sites now checked more than personal email

Research by Nielsen Online ranks "member communities" as the fourth most popular online category -- after search, portals and PC software -- and are now visited by 67% of the global online population.

The report, called 'Global Faces and Networked Places', shows 30% of internet users across nine markets visit Facebook monthly, a figure that rises to 47% when looking at the UK alone.

Other findings in the report show that globally one in every 11 minutes spent online is spent on social network and blogging sites while in the UK that figure stands at every one in six minutes.

The growth in social networks is not coming from the younger generation, but from the 35-49 year old age group, who made up the biggest increase in visitors during 2008.

On the mobile side, it is the Brits who are most mobile-savvy, with 23% visiting social network sites through their mobile handset, an increase of 249% since last year, compared to 19% of Americans, up just 156%.

Nielsen hoped to provide insights into the changing size and composition of the global social networking audience with a view to helping advertisers and publishers take advantage of the social networking phenomenon.

John Burbank, chief executive of Nielsen Online, said social networking had become a "fundamental part of the global online experience".

Burbank said: "While two-thirds of the global online population already accesses member community sites, their vigorous adoption and the migration of time show no signs of slowing.

"Social networking will continue to alter not just the global online landscape, but the consumer experience at large."