Sheryl Sandberg, Chief Operating Officer of Facebook, speaks at a Facebook event for marketing professionals, Wednesday, Feb. 29, 2012 in New York. Behind her is a projected cartoon by Peter Steiner ... more 
Sheryl Sandberg, Chief Operating Officer of Facebook, speaks at a Facebook event for marketing professionals, Wednesday, Feb. 29, 2012 in New York. Behind her is a projected cartoon by Peter Steiner with a caption, "On the Internet, nobody knows you're a dog." New, potentially lucrative advertising opportunities are coming to Facebook as a prelude to its initial public offering of stock. The idea is to lure big brands with the promise of effective, precisely targeted ads that reach the social network's 845 million users. (AP Photo/Mark Lennihan) less 
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Associated Press | Photo By Mark Lennihan
Wed, Feb 29, 2012 4:39 PM EST