The movie was garbage, the book might as well have been a picture book. I really can't say I care about anything else to follow.

I agree. While I read it at breakneck speed, it took me a few hours later to realize how logically flawed the whole mess was.

Brown's success lies primarily in hinting at something mysterious through a character's dialogue, prompting the reader to speed on ahead to figure out just what the hell this "mysterious thing" is going to turn out to be. For instance, in The Da Vinci Code, the female lead character there keeps hinting at some weird thing she caught her grandfather doing. I could not put the book down because I so desperately wanted to figure out what this was. Its a cheap trick to keep the reader interested that any pulp mystery writer knows and uses A LOT, but it is effective.

Obviously, the other reason for the success of these novels is their controversy. Reading it makes you feel like you are throwing the Vatican and conservative Christians a giant "fuck you." This may be, but on their own merit, they don't offer much but a few cheap thrills. If you want cheap thrills and flawed plotlines, read Dean Koontz.