About two years ago, I couldn't understand how people would want to read e-books. I had actually made it through a couple on my computer, but it was slow and annoying. My eyes hurt from the screen, my neck hurt from the angle I was holding my head at to read the screen, and my fingers hurt from scrolling down. Give me a nice paperback any day.
Then last year I got an iPhone, and more importantly the Kindle app. Suddenly reading e-books was doable. Not only that, but it was really handy having a book (or twenty) with me all the time. It made reading in lines, while waiting for a student, while grabbing a sandwich easy. In fact, it made it easier than reading a book, because an iPhone is a lot lighter and only takes one hand to operate. I think I may actually be reading faster, as turning the pages is quicker...
The circle was complete earlier in the year when the new Kindle was announced. Being incredibly curious about what all the fuss was about, and able to afford it for the first time, I pre-ordered one in August.
It came in September, and I have been taking it on trips with me. Instead of three or four paperbacks, I just have one slim device. The battery lasts longer than I need it to, it can hold stupid amounts of books in it, and it is almost as easy to read as my iPhone (and more comfortable). I even got used to the annoying flicker as it turns a page so that I don't notice it any more).
I find I no longer want to buy books. My collection, built up over years, is now something that I want out of the house (dusty and bulky as it now seems to me). I suspect the same thing will happen with comics, books, and magazines once I get an iPad or similar device.
Looking at the prices and adoption rates of e-readers and tablets, etc. I reckon paper-based reading materials only have about a decade left before they become specialty, expensive rarities.
It only took two years to convert me completely.