I've tried not to read too much of this because I am seeing the film tomorrow. But for those of you who think that realism was never a huge factor in the Indy films, is something I disagree with.
The progression in each of the Indy flims is very much one from natural towards supernatural at the end. In the beginning you think, "Well the ark is just a box," or "Eternal life, no wai!?" or "Magic rocks don't kill a village, whatever." And in this respect Indy was always a character who in the films usually got by off the skin of his teeth. That being said, as the films continue through thier plotlines, the lines between the realism and the supernatural are blurred, until the climax at the end when they are altogether broken. An example of this was in Raiders, when you see that the swastika wsa burned off the box while its in cargo in the boat, or in Temple of Doom when he pulls the guy's heart out and its still beating. Part of the big suspense of the films revolves around the fact that it is not clear weather or not the McGuffin is actually magic, like how in Raiders the ark is opened to reveal nothing but sand inside.... that is, until the transition between the natural and supernatural is broken, and the superstitions are confirmed. And because Indy is an expert in the Occult, superstition is where he knows his stuff, and its usually at this moment that he resolves the main conflict of the story. (says the chant to set the stones on fire, picks the right Grail, keeps his eyes shut through the crazy nazi-death scene).
So yeah, the idea of realism actually plays a huge role in the Indy films. Indy is also not some kind of superhero and there is a moment in each film when Indy is vulnerable, helpless, and on the edge of death, and usually, literally, hanging on by a thread (Raiders: the truck scene, Temple: the voodoo scene, OR the bridge scene, Crusade: the tank chase). He usually gets shot, stabbed, poisoned, set on fire, thrown off a cliff, or something like that. He's not meant to be some kind of Stephen Segal type action hero, because that doesn't fit in with the progression of the film. Indy is the realism, and the McGuffin is the supernatural, and as he gets closer to it the idea for the viewer of what is possible is supposed to diminish.
Now if this film doesn't at least hold to that established setup, I can see it being a total disappointment.