I think the reason for all these debates is we've been spoilt by technological development. We've always gone for shinier brighter and newer.
However, in the case of e-ink, I think they've got it pretty right already. I have no problems with it and don't need a LCD. If possible, Colored e-ink may well be something useful.
I'd focus on getting the formatting right. I would love it if the firmware on my Kindle 3 or reader would be smart enough so that when I chuck on a file of any kind and the pagination of the page is perfect. Now that would be something!