SAN FRANCISCO - APRIL 14: Twitter COO Dick Costolo speaks during the first annual Chirp, Twitter Developer's Conference April 14, 2010 in San Francisco, California. It was announced that Twitter ... more 
SAN FRANCISCO - APRIL 14: Twitter COO Dick Costolo speaks during the first annual Chirp, Twitter Developer's Conference April 14, 2010 in San Francisco, California. It was announced that Twitter chief operating officer, Dick Costolo, is now chief executive replacing Evan Williams October 4, 2010 (Photo by Justin Sullivan/Getty Images) less 
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Getty Images | Photo By Justin Sullivan / Getty Images
Tue, Oct 5, 2010 6:50 AM EDT