The most interesting aspect is that the substance alters reflected light, instead of transmitted or emitted light, like all other dynamic displays have since the CRT. It could be used to finally make a display that uses subtractive pigments rather than additive light frequencies, except for one slight problem... the fact that the article doesn't mention any means of regulating the stuff's opacity. Without that, you might be able to control the hue, but there's still the saturation and luminance to consider.

As I thought after reading Tat's comments - reflective might not make it a replacement for LCD and other screens. Like to surf at night with the lights off? No dice here.

That can probably be overcome, especially with the ability to reproduce all the colors of the visible spectrum instead of creating 3 and manipulating those could promise to be very cool - as long as the processors can control magnetic fields well enough at a pixel level.

If you want something that glows, we have so many different kinds of illuminated display it's not even funny. An actual reflective dynamic pigment, however, would make stuff like "cloaking devices" a reality, though. No matter how fast your image processor is or how fine the resolution of your cloak's surface gets, if it has to give off light or be backlit to look like anything natural, it's a dead giveaway.

That is, if pigment opacity could be controlled. That's really quite a lot more important than producing a continuous palette... as the old painters knew, you can form a continuous palette just by blending three or four colors in the right amounts. If I could create a reflective substance that only came in magenta, cyan, and yellow, but whose opacity could be changed dynamically over a wide range from a solid color to mostly transparent (hell, just 200 or so subdivisions would work), I'd revolutionize "stealth technology" overnight.