I know a lot of people look down on Dan Brown as an author but, in my opinion, his books are fun, exciting, and even educational (at least for me, who knows very little about symbolism and such).
This book was just as good as the others in the series. It was fast paced, the content was really interesting, and the mysteries remained that way until the end. All this made it very difficult to put down and, though I started it a month ago, I read the last 80% in the last 3 days.
The one complaint I have is some of the conversations between the characters are a bit unbelievable. When someone is in a time crunch to pass information on, they wouldn't speak in code or wait until their companion figures it out themselves. This made it a bit clunky in parts. Because of this, I give the book a 4 out of 5.