After Christopher read this, he told me I would probably like it. Since I had an old copy I hadn't yet read, I decided to give it a go. Chris summarized it well in his earlier review, so I'm going to give only my thoughts about it.
It was quite different from the movie, probably to the extent that a new movie could be made and be almost entirely different.
It's interesting to see how the 60s' mindset of "anything goes" being equivalent to real freedom is portrayed in the changes McMurphy makes to the ward, and also to see the general disdain for authority exhibited throughout (Not that the authority needs any help to be disdainable, since Nurse Ratched is one of the most easily hateable antagonists in recent memory.)
Chief Bromden narrates the book, and his story is easily the poignant.
And, I think that's it for me.