okay, saying the book is overated because the writer isn't that good of a writer is completely wrong. you obviously think the story itself is good, as does many people... but most people agree with you, including many authors, that Dan Brown is not a good author in terms of literary ability, and are surprised as how well the book sells even though its not written the best.
i have not read it yet, and not sure if I will now that I saw the movie. yes the book is different, but I have trouble reading a book after watching the movie. i am better able to read a book and then watch the movie.