Oh, wow. Easily one of the most interesting books I've ever read, even if it was dumbed down a bit for non-technical people. My only beef was with the last chapter, and that's because I thought the author was a bit too specific about things that are still classified - not because I had a problem with her explanation for Roswell (as some reviewers do).
I've never read so many passages of a book aloud to my significant other. If you have any interest in aviation, nuclear, or space history, just read it. I wish my copy didn't have to go back to the library this week...