Facebook opens up to 3rd-party developers

Facebook announced Thursday that the No. 2 social-networking site is allowing software developers to create applications, or "widgets," for Facebook users. MySpace executives may yawn, but Facebook is also going to allow other companies to open retail services and advertise on the site, Facebook founder and CEO Mark Zuckerberg announced at a media event here Thursday.

"You can serve ads...or if you don't want to advertise, you can just sell something," Zuckerberg told an audience of journalists and outside developers. "You keep all the revenue."

This contrasts sharply with MySpace's philosophy. It's against MySpace rules for anyone other than MySpace to advertise on the site.

At the core of Facebook's new plans is the debut of Facebook/f8, a platform that allows anyone to build applications for social computing. The company is hoping that its 23 million monthly users and the opportunity to create for-profit businesses will attract developers to build a host of new networking services on top of the f8 infrastructure.