I know, they cant always make the movie like the book. The problem is that they changed a great many things from the book to make the movie. And the greatest tragedy of it all was they stripped out huge 80's nostalgia and reference that were within the book, even when not obvious the author was always sneaking in 80's stuff (his own little easter eggs). They did stick in pop culture reference, but not like how the book did it.

As a movie, its just another action flick with great graphics. The casting was just fine and the actors did a fine job, but stripping out the 80's (Spielberg did sneak in what he could, for example there are a couple times when you hear "back to the future" sounds) really brought this movie down from what could have been a really rad movie.