EMR is the patented technology the expensive wacom tablets use and licenses for tablet PCs that need battery-less pens.
To say that it increases the precision from using fingers on a touchscreen is as much of an understatement as saying that it will increase the price of the device.
I came up with the "ePaper" display solution because there will always be some obscure document format that an eBook reader never will support. Looka at the portable media players out there; how many of them supports Flac, Ape, Musepack or even Ogg? Not many. The interface and the rendering of the displayed content will most likely be sluggish due to circuitry that is adapted for long battery life on the expense of performance. Most laptops are not as convenient as a book in terms of weight and size, and a TN laptop display is not really known to be friendly to read text on.
So the simplest solution is to let the eReader take advantage of the computational power of a nearby laptop or stationary computer, and merely use it as a touch screen with the advantages of being lightweight and readable as a newspaper in broad daylight.