The first screenshot is without a doubt a pre-render. Look at the arm and look at the texture quality.
The second could be an in game shot and if you told me this was a PS3 or 360 game I wouldn't have too much trouble believing you but I don't believe that's an in game Wii shot. Look at the texture quality, the shadows, the dynamic lights, and the cloth sims. I love the Wii to death but I don't think it could do all that and make something that looked that good. It could probably do any one of those things but not all.
The third one is obviously another pre render. Look at the blurred grass in the foreground and that's all you really need. There are ways to do that kind of stuff in game but I don't think the Wii could do that *and* produce something that looked like that real time.
Still though, those may all be pre renders but they look amazing. They look like they're starting to capture a really nice atmosphere and they got me interested. I've never played (or even heard of) a Fatal Frame game before but those screens did a very nice job of getting me interested in the game.