I read on my Samsung Galaxy Tab 10.1 and it looks fine, no eyestrain. I can adjust the colors and brightness and all that, I find that a slightly dimmer than normal black text on sepia background is pretty easy on the eyes. Although I agree that for just reading the e-ink is even better.
I don't anyone wants or needs iPads to go away. Someday, just like the current smartphone and PC markets, Apple will own a few percent at the profitable end of the market and everyone is happy.
I'm looking forward to some hands-on time with the Sony S2, I think a folding screen if implemented well can be the best of all worlds, fits in a pocket yet magazine size screen.
My biggest problem with the Amazon Fire is the unfortunate name.