I think those that didn't like it are those that haven't read the book. If you think about it, there isn't really much action within the plot of the book, more like Langdon explaining various concepts and theories in a series of real-time and flashback moments. I'm pretty certain if you have read the book, you won't be disappointed in the least. There are MILLIONS of little details in that book that no 2hr movie can do justice to.