But that's my point -- the contrast for regular black and white text is so much worse with color eInk than it is for regular black-and-white eInk.
It seems like a terrible tradeoff to make, for colors that are still terrible.
Reading a graphic novel on a color e-ink reader will be so washed out... if you really want the color, it seems like you still have to just read it on an iPad etc.
For some specialized uses, sure: think about researchers wanting to look at illuminated manuscripts, especially wanting to see marginalia and the like. A large, low-eyestrain way of seeing high-quality scans would be very handy.