Drawback to a vigorous and spirited Presidential primary, I suppose: you miss the important news. As I understand it, they wanted Matthew McConaughey to play Roland, only he wanted to play the Man in Black, because, let’s face it: that’s a pretty sweet villain role to have. Maybe not a Christopher Lee-level villain role, but it’s definitely an Alan Rickman-level one, and you could see how an actor might want a shot at it. So they ask Idris Elba, who of course took the role.
Now, all of this means that they’re gonna have to rewrite Susannah’s character a little, of course. But it’s probably not going to have to be too much, and besides: Idris Elba. I’d cast him that role myself.