+1 for this interesting suggestion. Thanks. I've never heard of it and would love to try one.
Apparently, it doesn't scroll, but I'm sure scrolling takes a lot of energy to do all the refreshes. I assume that a large, hi-rez reader can offer scrolling, thinness/lightness, or long battery life, pick two.
Have you seen the Sony Digital Paper System[0]? It seems to fit the bill perfectly but the price point high.
[0]: http://pro.sony.com/bbsc/ssr/product-DPTS1/?PID=I:digitalpap...