I'll admit that I'm not familiar with The Dark Tower all that much. I used to work with a guy who assured me that it's arguably King's best work ever (I'm pretty fond of The Stand, myself), so I'll have to wait and see (like so many others) whether or not this Fantasy-fueled tale of good versus evil lives up to all of the hype. The trailer is kinda meh, and I'm not all that thrilled with the featured dialogue, but -- as I've often preached -- don't affix too much faith to trailers as they're generally created by advertisers and not the involved storytellers.
In any event, here's the trailer: