It's a huge comment, so here's the relevant bit:
"What Cameron has been doing with Avatar is to shoot in deep focus (no using the aperture and focus controls to blur out the background, a favorite technique for isolating the subject from the environment) but instead create depth by altering the angle between the two lenses dynamically, creating the illusion of a large space in which attention to depth is focused stereoscopically. Until now most 3d projects have kept the stereoscopic distance fixed, which yields the feeling of watching the story take place on a stage in front of one and occasionally having one of the props or actors protrude outwards toward the audience. By varying the angle between the lenses in the same fashion as our eyes, Cameron presents a far more immersive way of experiencing the third dimension."
To your main point: The 3D still didn't feel completely natural. I did not feel like the camera was forcing me to focus on anything in particular, but I did feel like the whole thing was slightly blurry. Maybe it was my position in the theater (off to the right side of a huge Imax screen, rather than dead center), but it detracted from the experience because I wanted to appreciate the details and they were often fuzzy due to imperfect alignment of the images.