Sure we take e-ink into account... plenty of others on this forum swear by it. But there are also plenty of us who are perfectly comfortable reading smaller screens and LCD screens, and would be perfectly happy with smaller devices.
Obviously, an iPhone is not the reader for you... and that's cool. But there are still a lot of us who see the value in iPhone readers (or, at least, their potential). Hey, e-ink ain't even got color yet!