Its difficult to find the details on this because these companies are so secretive, but from everything I have seen, the e paper technology we have is completely useless for anything but displaying mostly static content. The refresh time is insanely slow so simply typing text or scrolling a page would be almost impossible.
Also almost all of the full color eink screens I have been able to find details on are actually just normal TFT LCD displays with some matte film over the top. The core eink tech seems to be fairly easily changed to get 3 colours at the cost of 15 second refresh times but any more colurs seems unlikely.