Facebook CEO Mark Zuckerberg speaks at Facebook headquarters in Menlo Park, Calif., Tuesday, Jan. 15, 2013. Zuckerberg introduced “graph search" Tuesday, a new service that lets users

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Facebook CEO Mark Zuckerberg speaks at Facebook headquarters in Menlo Park, Calif., Tuesday, Jan. 15, 2013. Zuckerberg introduced “graph search" Tuesday, a new service that lets users search their social connections for information about their friends’ interests, and for photos and places. (AP Photo/Jeff Chiu) less