OCCUPATION: Facebook founder
PREVIOUS APPEARANCES ON THE TIME 100: 1
PRO: With Facebook's population inching toward 200 million even your grandma's on it, though her status updates are usually pretty lame Zuckerberg is managing the fastest-growing social-networking site on the Web.
CON: A recent dustup over the site's terms of service many feared their tipsy Wall-to-Walls might become permanent Facebook property demonstrated just how quickly users could turn against Zuckerberg's creation.
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