Personally, I'd never be able to have a Kindle. I understand that they're really practical, especially for traveling, and I do travel a lot, in fact. Admittedly, it would be loads easier to have it all stored in a digital space instead of lugging 5 hardcover books, but I live in the paranoid belief that the world is being taken over by electronics. Also, the feel of paper books is a lot more comfortable between my fingertips than a flat, glassy surface. I like my paperbacks. And who cares if they're old and ruined? It means I've read them too many times.
But, that's just me. I can see the practicality, and I get why it's been such a big hit. On my last airplane flight, I walked to the bathroom and saw four Kindles on the way XD You can even download books in Cyrillic, Greek and Japanese , which I'm actually pretty impressed by. But, still, I prefer paper. Besides, 'It was a cold, rainy day so I curled up with a Kindle' sounds so wrong to me xD