It's honestly kind of shocking that it took this long for Portal to get an art book of some kind- but it just might be worth the wait.
Valve and Dark Horse pull back the curtain to give you a backstage tour of one of the most innovative video games of the decade! The Art of Portal 2 walks you through the visual evolution of the award-winning game, from concept to completion, with never-before-seen concept art and insights from the writers and artists behind the Portal series.Stunning fact: 4 million plus copies of Valve's Portal 2 have been sold since the game launched. Pretty nutty for a title that has almost no violence, is loaded with humor, and is basically a puzzle game at heart. Cool stuff.