I still don't get what the hell were they thinking casting Tom Cruise in the first place. Not that he's not a capable actor, but one of the most notable aspects of Reacher's characterisation in the books is how tall he is. "Tall" is the last adjective I'd think of to describe Tom Cruise. The fact that they didn't even get that rather important detail right doesn't give me much hope that they'll get anything else right. Which is a shame, because the books I've read in the series (Die Trying and Tripwire, plus most of Without Fail [I have about seven chapters left]) were fun thrillers that would translate well to the silver screen in the hands of someone who knew what they were doing. And they already have a gigantic audience - I can't think of any other series that sells as many books in our store right now, except (shudder) Fifty Shades of Grey. I'm not even sure A Song of Ice and Fire sells as much as this series, and they have that on its own table.
That said, the books wouldn't be half as fun without Child's digressions into things like ballistics and military strategy, and there is definitely no way to translate those to film format. So maybe it's for the best that the books look set to stay the definitive rendition of this series.
The trailer looks decent enough, apart from the fact that there is no way I am ever going to believe Tom Cruise is Jack Reacher, which kind of kills the whole effect. It also revealed next to nothing about the plot, and didn't even hint at Reacher's Sherlock Holmes-like mental faculties. But I guess there's only so much you can give away in a two-minute trailer.
Unless this gets particularly good reviews, I'm probably going to stick to reading the books.
The mystery series I really want to see get a film adaptation is Jo Nesbø's Harry Hole series.