If you are a serious novel or non fiction reader kindle is the best option for outdoor reading. If you want more than just a book reader the iPad is the ultimate anti boredom machine, it's like having 25 devices. One of the downsides to the iPad is there are so many fun thing to do with it many find it hard to concentrate on reading a book when Angry Birds is just a couple taps away.

I have a kindle V2 but haven't touched it since I got an iPad the day iPads were released. I do have about 2 dozen books on my iPad many of the books I buy are illustrated and look much better on the iPad.

I was just on vacation in Aruba, I saw a guy sitting on the side of the pool reading a kindle as well as several other kindles on lounges chairs around the pool. I didn't bother bringing my iPad down to the pool or beach I spend most of my time in the water.