The E.Ink display is monochrome, has horrible refresh, can't even imagine doing full-motion video, and is only 5 inches diagonally after 5 years.
Something flexible or plastic might eventually make it. This is not going to be it. The nature of the technology makes it a poor contender for FMV.
Anthony, I believe some OLED variant could be built with a clever edge connector to allow nearly infinite, seamless tiling. I hope that product is real within 5-10 years. Instead of building huge cinder blocks, build the nearly perfect small "brick" and the walls will follow.
I am envisioning a 16 x 9 panel that is perhaps that many inches in size with a 960 x 540 pixel count or so... High fill factor (OLED should allow this), flexible substrate... Corner connectors, top right, bottom left on ribbon cables to join with the two adjacent pieces if needed... They all feed back to a single controller that identifies the panel count and then scales the image as needed based on the total pixels...
You could make a seriously booty-kicking display out of this...