I know this topic will likely get contentious with some people posting studies that LCDs in NO WAY cause eyestrain, and vice versa. However, I loved the way you phrased the poll as a personal preference.
As for me, I am a corporate attorney and I stare at a lovely flatpanel LCD computer monitor for ~10hrs a day. I used to go home and read on my palm pilot or blackberry. And then my lovely and beautiful partner got me a Nook. I find now that I can read for hours on top of the LCD screen use because it feels, to my eyes at least, like I am looking at a DTB page. I get headaches far less and find that I can really enjoy e-reading again in a way that I had not been able to since becoming an attorney nearly five years ago.