Note that there are those of us who read a lot who can't stand e-ink screens; at least the previous generations, I haven't had a chance to assess the current generation. Every past e-ink reader that I've picked up, I had to put down after a minute; I could not stand the screen going black to refresh. I currently use a Galaxy Note, which is great for reading in everything but full direct sunlight; some use of an Archos 70, which is so-so, but usable.
The Archos tablets might be something to compare to the Nexus 7, though still at an older version of the OS; at least on the 70, Archos provided the possibility of installing Angstrom Linux (haven't tried that yet), so reasonably open compared to even older Archos systems. Not at powerful, but also cheaper... At any rate, the Archos is what occurred to me after I read the specs our editor provided for the Nexus 7.