I get a lot of questions on what tablet I use / prefer (iPad Mini) and if I still carry an e-reader when I travel. I do and I'll tell you why. To put it simply, my daughter has taken over my Mini. Some other quick thoughts are that the Kindle Paperwhite is lighter than the Mini 95 grams, the front light is amazing, the resolution is crisp, and lets not forget about the amazing ecosystem than Amazon has established.
I've never enjoyed reading on the iPad unless it's a news article or a magazine through Flipboard. I also end up getting distracted by all the applications that are on the iOS ecosystem. When I want to read a book and dive into it, I'm still in enamored by my Kindle. In fact, my wife prefers it too!