With or without reading this book, you'll be extremely disappointed by this movie. It lacks crucial elements that ties the movie together, and the actors lack the necessary chemistry to make this movie what made the books a phenomenon. It didn't match the book at all and left out some of the most dynamic scenes. The cinematography was extremely poorly done, and the overall feel of the movie was cheap. Even with the budget they had, they could have done better if they were to have stuck to Meyers's original vision.
Even if you think Edward is the sexiest being alive, you won't like Twilight the movie.