• by Mark Walsh  @markfwal, December 10, 2010

The update of Facebook's official statistics page highlights how the social network is expanding its reach via initiatives like Facebook Connect, Open Graph and social plug-ins such as the Like button.

The new topline stats show Facebook has more than 500 million active users, half of whom are logged on to the site at any given time. People spend over 700 billion minutes a month on Facebook, and the average user has 130 friends. The site has more than 200 million active mobile users, and those users are twice as active as Facebook members on the desktop.

Facebook's efforts to grow through integration with third-party sites, however, is where the company is seeing the fastest growth. It now has more than 250 million users engaging with the site through Connect, the Like button and other social plug-ins. That's up from 150 million in late June and 60 million in February, according to Inside Facebook.

"Connect has been around for years, but Facebook's renewed efforts to build on it with the plug-ins and Graph API has quickly paid off. With its big and growing portions of off-site users, Facebook has the opportunity to integrate even more of its features, like Credits and ads, with everywhere users are," noted Eric Eldon in a Friday post.

Since the launch of the plug-ins and Graph API in April, an average of 10,000 sites a day have been integrating with Facebook. Some 2 million sites use the plug-ins, up from 1 million in June. That total includes 80 of comScore's top 100 U.S. sites and more than half of the top global 100.

Facebook also revealed that its users install 20 million applications a day. In terms of interaction on the site, the average user is connected to 80 community pages, groups and events and creates 90 pieces of content a month.

Facebook has continued to extend its push across the Web through more recent projects such as its partnership with Microsoft to create Bing Social. It allows users to view "Likes" and content on Bing generated by Facebook friends. But the move into social search and Facebook's overall effort to make the Web social carry parallel privacy concerns.

The social plug-ins, for instance, collect data such as the Web page visited and Internet address of the visitor as soon as the page loads even if someone doesn't click the Like button and whether a Facebook users is logged in or not. Facebook has said it doesn't correlate pages viewed with advertising, so someone reading articles about vacationing in Mexico won't see ads for hotels in Cancun.

If someone does click on the Like button, however, that data is added to their profile and they might see a related ad. Facebook has also come under criticism for its instant personalization program that shares information about Facebook members with outside sites, including Yelp, Pandora and RottenTomatoes, by default.