Who is that woman on Jonathan Franzen's 'Purity'?

Jonathan Franzen's new novel, "Purity," won't be released till Sept. 1, so we've still got three weeks of staring at that young woman staring back at us.But who exactly is she?Rodrigo Corral, the creative director at Farrar, Straus & Giroux, is cagey. "She's a friend of the photographer's," he says, "and wishes to remain anonymous."