The Facebook Effect is about the product and company Facebook, as opposed to Zuckerberg, per se. In tone, it more closely resembles business non-fiction, or long-form journalism, than the celebrity biopic style of The Accidental Billionaires, on which the film is based. So it's less fun as beach reading, but in my opinion more accurate, and probably of more use to somebody in the business.

Kirkpatrick had unprecedented access to much of the early team, including people who were no longer with Facebook. He does come off as slightly star-struck at times, and not just at Mark Zuckerberg, so keep your salt-shaker handy.

Disclaimer: I work at Facebook, and am proud to call Zuck a friend.