Frankly, I don't know why someone would choose this over reading on your smart phone. (Assuming you have a smart phone.)

I bought a nook, but then returned it after discovering that its pdf support sucked, and that I could read much more easily using Aldiko on my nexus. I find e-ink screens to actually be much worse for reading compared with white text on a black background on a hi-res LCD/OLED. The page turning time is a deal-breaker compared with a smart phone. That e-ink KACHUNKA every time gives me a headache for some reason.

To me, battery life seems like the only selling point.