By the way, there are several apps already which build 3D scenes from two separate pictures. Some can even generate 3D models. HDR used to require manual exposure bracketing in phones too. Now technology has caught up.
Correct me if I'm wrong, but the Lytro stereoscopic field looks fixed at a relatively short distance. At the moment it seems to be a very subtle parallax effect, one that might be mimicked by an ever so slight movement of a camera sensor.
Edit: after a bit of digging, it looks like they make the micro lens array themselves and buy the sensors without one. This obviously makes acquisition easier, but as the pixel pitch decreases ( by an order of magnitude, to compete with a modern SLR ) the complexities of building and attaching that array increase significantly.
The cool thing I saw about Lytro isn't their flash based player. Its the idea of giving you another degree of freedom after a picture is taken. Like colour correction, you can do focus correction, DOF correction, etc. I would still export one flat image as a result, but gaining that flexibility without carrying around a monopod to take 10 bracketed images is awesome to me.