Saw the movie a couple of nights ago, and have read all the Jack Reacher books except the latest one (just haven't gotten 'round to it). I didn't think it was all that bad. A little slow getting going, but if you don't focus on Tom Cruise's physical differences from the book descriptions of the character, they did a decent job with the adaptation.
My wife on the other hand thought the movie was really bad. To each their own!