[smilekzs]

Except that eInk has been around for decades without much breakthrough you'd see in even LCD/OLED technologies. This cannot be easily explained off as lack of R&D investment. IMHO the scalability is the biggest hurdle. That, and the lack of even basic coloring, let alone full CMYK.

[jimktrains2]

It's not even color. A letter or a4 sized tablet is out of the price range most people. Especially grad students or recent PhDs who'd have a huge use for it.