About the eyes strain: as I said at everyone its tastes, but from my experience I developed the strong suspect that the notorious color LCD backlighting eyes strain is frequently a... pigment of immagination (my apologies to Pratchett for the theft...
I started reading ebooks back in 1993 on a Newton MP0 (a Sharp ExpertPad really, but that is another story...
. If some of you ever used that generation of PDA he\she will know what mayor pain in the... eyes those screens were!
Along 15 years I used all the Newton models (100,110,120,130, 2x00), a Rocket eBook, iPaq 3130, 3630 & 5450; Sony Clie' NX80 & NZ90; various Palm from the original PalmPilot to a couple of Treo; Nokia 770, 7710 & E61i, a Sony Reader, plus some other models of PDA and smartphone that I believe noboby knows today (Amstrad PenPad anyone? Hmmm... maybe I should start to consided to sell my collection...
I have not done this list to show-off (ehm...
but to say that I really used a lot of different kind of machines with different type of screen and functions ensambles. And my personal conclusion is that, at least for my way of life, nothing beats for now, as fullfillment of all my necessities of info-fruition on the move and as well when reading in bed, a smartphone with an ample and backlighted screen.
When the e-ink technology will give me a screen with not-ridicoluos refresh times and optional backlighting for when I decide that I need to use it (and color maybe), I will gladly buy it and use it as my main mobile info-machine. Longer battery life and lower temperature ar not enough. IMHO the Readius is a really good step in the right direction, expecially for the foldable screen, but no-cigar-yet...
Beside the screen considerations, my perplexity about a dedicated readers for ebooks is centered on the core of the ebook concept. In my opinion a dedicated reader is just like the first cars. They were designed not as a new mean of locomotion, but as horse-carriages whitout the horses. Mind the Ford Model-T.
Ebooks are IMHO a new way to access info, and replicating the paper book paradigma is an epistemological error. I don't care for the book as a fetish, I want my info as ready to be fruited as possible! And I want them integrated and integrable with hypertextual access to other info, and all this without cluttering my life with another piece of plastic. Ergo, the smartphone.
We can discuss the right screen dimension and quality of the aforementioned 'phone if you wish, but a dedicated machine is a no-go, with eink of LCD does not matter. And not let me even begin about DRM and similia and how a dedicated and proprietary machine is more useful for a centralized control of contents that for its useful distribution...
My apologies for the long rant and for my grammar errors (I'm not an english native spek... ehr, writer I mean...