I really would be more excited if they'd cast someone more Reacher-ish. Adam Baldwin is who I have in my head when I read the books, but I'm not naive enough to think that they'd cast someone like him to topline a big Hollywood movie. But Chris Hemsworth, Alexander Skarsgard or even Ben Affleck would have provided the requisite size and bulk if they'd wanted to get a box-office draw.
Leaving that aside, I do think that this will be a good movie. McQuarrie is a fine writer and director and I really like Cruise as a leading man, even if he's not my idea of Jack Reacher. I'm not out-and-out excited but I am looking forward to seeing this and interested in seeing how Lee Child's plotting, which I think is deceptively good, translates to the big screen.