If I were a bigger fan of Star Wars, I would buy this and read it in bits and pieces over time, but as it is, since the library didn't let me keep it for very long, I skimmed it in a weekend. But it was a very fun skim.
Star Wars is not one of my main nerd-realms, but I will always have a spot in my heart for those original three films (yeah, me and everyone else) and so seeing how the middle film was put together, warts and all, was extremely fun and rewarding. The book is beautiful and comprehensive, and the concept art... God, I think I like the old concept art more than I like the films. It's all very fun and absorbing, and I can only guess how I would wet my pants over this if I was a Star Wars-nerd.