Social networking website Facebook has capped a year of phenomenal growth by overtaking Google's popularity among US internet users, with industry data showing it has scored more hits than the search engine.

In a sign the web is becoming more sociable than searchable, research firm Hitwise said the two sites accounted for 14 per cent of all US internet visits last week. Facebook's home page recorded 7.07 per cent of traffic and Google's 7.03 per cent.

It is the first time Facebook has enjoyed a weekly lead over Google.

The lead may be slim, but it has become inevitable as Facebook's popularity has grown rapidly from just over two per cent of visits a year ago. Heather Dougherty of Hitwise said Facebook had “reached an important milestone” with the weekly figures. It had hit the daily number one spot onChristmas eve, Christmas day and New Year's day previously.

Facebook's rise had been impressive. Its membership has more than doubled in the past year, passing the 200m mark last April and 400m in February.

Google has responded to the ascendancy of the social networking site with introduction of its own Buzz service last month. Buzz allows users to add status updates, friends, pictures, videos, location information, comments and links to other networking sites.