A spinoff from another thread... but I generally like movie adaptations! I thought Lord of the Rings was well done, and I was really impressed by the second half of the Harry Potter movie franchise. I wasn't that impressed by The Golden Compass, but thought it was a tough book to adapt to film.
I don't get really worked up if minor details change from the book to the movie though... as long as I can work out why they made the changes. If it's a random change that doesn't really matter, then that'll usually bother me when I watch a movie.
Do you generally like movie adaptations of books? Or do you worry that Hollywood will ruin your favorite book....