Vapor from an e-cigarette obscures the user's face in a London coffee bar. Dan Kitwood/Getty Images hide caption

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Jonathan Franzen, pictured here at The New Yorker Festival Fiction Night in 2009, won the National Book Award for his third novel, The Corrections. Joe Kohen/Getty Images hide caption

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A woman tries electronic cigarettes at a store in Miami. Joe Raedle/Getty Images hide caption

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