I use the first version IPad and really love it for reading books and other things. I have been a book lover for years, and have always had a pretty large library. But as I get older, I find the piles of books and magazines a chore to move around, clean up, dust and keep track of. I almost never buy a book now unless I can get it on Kindle or the IBook Store. I find I'm actually reading more than before. I used to think I would miss the tactile sensations associated with paper books. But I don't really. And it's so convenient for travel as others have said.
The one think I don't like about the IPad is the screen is really hard to read in sunlight. Though with my cover placed just so, I can do it. My wife had a Kindle and has no problem. Tempted to get a Kindle now that the basic price is down to $80 just for those outdoor reading experiences.