Reid Hoffman, left, the founder of LinkedIn, and Jeff Weiner, the company's CEO, celebrate the listing of LinkedIn, Thursday, May 16, 2011, on the New York Stock Exchange. LinkedIn, based in Mountain ... more 
Reid Hoffman, left, the founder of LinkedIn, and Jeff Weiner, the company's CEO, celebrate the listing of LinkedIn, Thursday, May 16, 2011, on the New York Stock Exchange. LinkedIn, based in Mountain View, Calif., is an internet-based social networking rolodex for business people. less 
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Associated Press | Photo By Mark Lennihan
Thu, May 19, 2011 10:38 AM EDT