I would put in another strong vote for Eink - I have tried long-term sustained reading with backlit devices and even the old Palm-like non-backlit LCD and also ended up with eyestrain. The first reading on such devices was fine but I always found something else to do instead of subjecting myself to reading again on these devices once the cool factor wore off.

With Eink (Librie, Reader, and now the Edge), I can read reliably without eyestrain. I am talking about years of usage on a consistent basis. I estimate a few thousand pages worth of solid reading on my Reader over the years that I had it (I sold it when I got the Edge). This may seem small compared to the 700 pages in one week for the ipad owner but I primarily used the Reader for bedtime or in-flight reading.

So for me, Eink has always been very worthwhile and my sole reason for picking the Edge was that it provided the best bang for the buck in terms of Eink screen size for the price. The other bonuses, such as the tablet functionality, Android, netbook replacement, awesome PDF functionality, etc. were just gravy that are of course much appreciated. What can I say, I am an Eink fanboy though I am keeping an open mind about the PixelQi display too.