Disclaimer: I am a reader of books only. I do NOT read PDF articles, charts, graphs, or even comics. Also, I have old(er) eyes that are very tired after work (use computers all day). And I read
a lot at night (2-5 hours). That said:
SIZE DOES MATTER!
After spending last evening reading on the DX, and playing with auto-rotate, text sizes, etc., I pulled out my K2. It looked and felt like a toy! And previously I loved my K2. And my K1.
The DX truly reads like a real book: fewer page turns, more text displayed per screen (fewer "Page Backs" to review dialogue or find character names), etc. -- what Jeff Bezos referred to (if memory serves) as the reading device disappearing and the reader entering into the book's reading experience.
Yes, it's heavier - esp. with the cover. But so are books (hard backs). I simply propped it either on my lap (with the cat's grudging permission), on the back of the cat (not for long!), or on the arm of my chair.
It ain't perfect yet, but as Eric Cartman would say: "Sweeeeeeeeeeet."