I read Kindle books on Kindle, iPod Touch, iPhone 4, Droid X and iPad. If I'm going to sit down and read for a long stretch, I definitely prefer the Kindle (I was a beta user of the original Kindle and have the latest). The iPad is too heavy to read comfortably. I've never used the Kindle DX but have heard the same complaints about that device. The Kindle 2 or 3 is the ideal size. can be held with one hand comfortably. Easy on the eyes. Very readable in direct sunlight.Reading on iPad (or any other back lit device) is better in low light. I use if often before going to bed with the lights off so that the light doesn't bother my wife. That's at most about 30 minutes of reading before I start dozing off. At night, I'm more likely to read on the smaller iPod Touch than the iPad. At $139 for the WiFi version of the new Kindle, I'd recommend it highly, even if you have an iPad. I would never buy books on iBooks if I can get it on Kindle. It works across all of my devices and Whisper Sync lets me pick up where I left off on any of my devices. Most people will have a Smart Phone and I'm sure Kindle will have an app for every major phone platform as well as PC and Mac. Not sure if iBooks will keep up. My entire library going forward will be on the cloud and can be accessed using any device I own. That's pretty compelling and will keep me going back to Amazon, even if I don't read all the time on a Kindle device. If Apple ever comes out with a 5 or 7 inch iPad, it could be compelling as a Kindle replacement. I don't really mind the backlight strain on my eyes. What I have a problem with is the size/weight of the 10" iPad compared to the much slimmer and lighter Kindle.