Way too long! Ipad's success can only benefit authors. The whole electronic books business is good for authors. What's not so good is the small percentage (I get 15 % on an e-book sale from Penguin) authors get.
As for book stores: the returns business has done a lot of damage to midlist authors. I'm finally out of that. My publisher does not accept returns. I guess that means there will be fewer orders, but I'd rather have that than the awful returns mess with reserves held against me on royalties. And I can't say that book stores have helped sell my books. On the whole, it's been the other way around.
As for Kindle vs. Ipad: I read in bed. It will be the Kindle for me. I'd hate to have the other thing fall on my face when I doze off.
The publishing industry is not changing what it is selling, ie books. it does need to change how and why it sells books, cutting costs, changing how it treats authors and making better publishing decisions. E books are just another outlet, an extension just like hardcover to paperback. This is one possible solution for the future of publishing, changing the selection process and thus the marketing possibilities: www.slushpilereader.com