Wonder though how much the video is doctored up. Looks like really fast e-ink. For that price ($120) someone should be able to make a complete phone sized ereader. Now that would be cool - a mini-kindle with frontlight and e-ink and 4 inch screen doubling as a mp3 player for music / audiobooks.
As a fancy and bulky case for iPhones, I doubt it will be much use though. I am definately not going to buy an iPhone only for this cover. Them promising to make it color-eink by 2014 (or trying to) seems a bit unrealistic as well.