Whether it's a Kindle or iPad, I think we all have an e-reader in our future. Printed books won't go away, the same way that TV or radio hasn't disappeared with the rise of Internet usage. But I think that avid readers will gravitate to Kindles and Nooks. With an e-reader, you can carry all your books with you. And e-books are cheaper in most cases than their print counterparts.
E-books are also better for authors. Writers like Joe Konrath are skipping the middleman and writing and selling books directly to readers, without publishers or agents. This allows them to make more money while selling books more cheaply to readers. His blog is fascinating on the economics of e-publishing - though I think that his results are atypical.
I wrote a book too, Murder in Ocean Hall. I published it myself, using Amazon's CreateSpace and Kindle Direct Publishing Services. One thing I've noticed is that Kindle readers are avid readers. They buy a lot of books. I've not sold a lot of books but I've sold more Kindle copies than print ones, because it's easier and cheaper on Kindle.
Irony: I don't have an e-reader yet! I've been debating between the iPad and the Kindle but will probably go with the Kindle due to its e-ink screen.