It didn't look that much better (or distinguishable, for the matter) than one of those reflective LCDs (e.g. Pebble's). And reflective "memory" LCDs also have almost negligible -- though not zero -- power consumption. Except for maybe signage products most people don't care about this difference, and LCD is way cheaper and mainstream, so...
It's no surprise that many manufacturers just put an LCD and try to get away by calling it "ePaper". There is a lot of geek appeal here, but I'm not really sure if we really need any new technology for "mainstream".
That is a really neat technique though, I hadn't read up on the details before.