'Social Network' Jesse Eisenberg: Facebook founder Mark Zuckerberg is 'a lonely person'

mark-zuckerberg-jesse-eisenberg.jpg Mark Zuckerberg, whose ambitious and calculating behavior during the creation and building of Facebook is dramatized in the new film, "The Social Network," has a staunch defender.

That's Jesse Eisenberg, the actor who plays Zuckerberg in the film based on the book "The Accidental Billionaires," a film that many feel focuses on Zuckerberg's flaws, his burning ambition and his often cruel treatment of friends and coworkers.