Facebook Holds Its Fourth f8 Developer Conference!

Facebook CEO Mark Zuckerberg delivers a keynote address during the Facebook f8 conference on September 22, 2011 in San Francisco, California. Facebook CEO Mark Zuckerberg shows off the new Timeline as he delivers a keynote address during the Facebook f8 conference on September 22, 2011 in San Francisco, California. Facebook CEO Mark Zuckerberg kicked off the conference introducing a Timeline feature to the popular social network.