One of my favourite books is American Psycho. The constant bored tone Ellis uses is stunning. I've never seen fiction handle boredom and disconnection so well. When the film came out I decided not to watch it. I couldn't see a movie replicating the things I admired about the book. The requirements of a Hollywood movie would sensationalise a book I loved for its lack of sensationalism. I didn't want this completely different work to alter the way I thought of a novel I liked.
I feel the same way about Watchmen. I love the book. I remember arguing for hours with friends about which characters were the most moral, who was 'right'. Then I watched the first trailer and heard Rorscach's voice. In my mind Rorscach speaks in a weasely voice, closer to his secret identity than the figure he cuts in costume. In the clip I saw he sounded more like the trailer-man.
I love the novel Watchmen. I love the way it's paced, the speed at which it unfold when I read it. I love the details in the background, the detours the story takes. Like Alan Moore I can't see these things working in a movie.
A couple of links from LinkMachineGo sum up two other reasons I don't want to see the film: the tacky associated merchandise ("we're society's only protection"?) and that it's not likely to be a good adaptation.
I hope everyone enjoys the film, it's just not for me.