The site launched in 2004 as a feature-light networking tool for students at Harvard, where Zuckerberg was an undergraduate at the time. It then gradually expanded to other colleges and then corporations before finally opening up to the public. Photo- and video-sharing was added. The "news feed" was incorporated. Then, last year, Facebook kick-started the Silicon Valley developer-platform craze by opening up its site to outside services--and now it's "iterating" again with Facebook Connect, an extension of the platform to allow Facebook credentials to be used on external sites.
"We just announced that anyone can now apply," Zuckerberg said. "We basically had a closed beta, and now we're opening it up."
"Opening it up" is key. Facebook, which is inaccessible without a user account, has come under fire for being too closed-off, as conference organizer John Battelle said as he led the onstage talk with Zuckerberg. The social network has declined to participate in OpenSocial, an open-source developer standard that Google organized and launched last year.
But going from closed to open is just part of the Facebook rollout, Zuckerberg said. "The main thing that I would say is that there's this very clear transition that normally happens from closed systems to open systems," the 24-year-old CEO explained. "In a mature environment, a lot of these technical systems end up being pretty open, but they also need to start somewhere."