I can't argue with what's been said. For me - and this pains me, in a general sense - the movie wins over the book. Darabont really did create something special with this film, and like Jim, if I come across it on TV I immediately throw down the remote.
I still have plans on posting more of my specific thoughts about the specific differences between the two, but overall, I'd say King's story is only slightly more "realistic" (I am mainly thinking about the periodic changes in the warden of the prison through the years and the relative isolation of Andy in the book as compared to the "group of friends," for lack of a better term, in the movie), but the way Darabont fleshes out many of the characters in the movie really adds an emotional level that elevates the film.
chris