With most of the major challenges tackled, this technology will surely bring the future of smartphone to next level - a smartphone with long battery life. The question is still coming down to the cost of the final product. Only time will tell.
The ability to create small geometry "reflective displays with vivid colors that can be viewed at nearly any angle" is an elegant development. In nature typically the colors vary with angle. An alternative approach would have been to use small colored spheres which would therefore maintain their color at all angles - but requires get good pigments and a larger scale.