One thing I noticed today after getting the iPad is the Kindle 1 and 2 are much lighter.

The iPad is pretty substantial. When sitting and reading a book I usually have it in my lap... When laying down and reading a book I usually have it laying down next to me or on my tummy. With the iPad... Nothing has changed... I read from it the exact same way. It does have the weight of a decent sized hardcover book... probably just a little less. It definitely weighs more than a small paperback though.

The weight on the iPad doesn't bother me as I usually have it on my lap or laying on the bed while I read laying on my stomach. Even the kindle is too heavy for laying on my back and reading while holding it up in the air for any decent length reading session.

This is a great app for the iPad. It works perfectly. There are quite a few books that the iBook Store doesn't have that are available at Amazon via the Kindle Store.