The next version is all about a bigger screen size. It is the main complaint right now with Kindle and there is a couple of competitors out there that already offer devices with bigger screens
I have the OK (original kindle) and the screen size is fine for reading books, but newspapers, textbooks, and perhaps pdf's would be a lot better with the bigger screen.
I personally prefer multifunctional devices supporting open standards and Sony reader beats Kindle in that respect. Kindle effectively locks you up to the 'approved' content exclusively supplied by the only provider 'of your choice'. Look what can happen to your $300+ toy if Amazon doesn't like you for whatever reason:
I follow the kindle discussion boards, and to be fair the case you link was resolved. The guy got his kindle back. Secondly, by his own admission, that guy had returned thousands of dollars of electronics purchases to amazon for which they reserve the right to cancel your account. Without an account, no kindle for you. Of course you can still read what's on there and upload your own content via a computer but no more buying from amazon.
I somewhat agree with your concerns about content, but you can access all out of copyright material not just through amazon. For example http://manybooks.net is an excellent source. Plus you can convert word, text, pdf's, etc to read on kindle.
The main advantage is instant wireless access to (eventually) all books. Sony doesn't have newspapers and magazines, which is the attraction for me. And they don't have wireless, yet.
Amazon's business model is to give you the device and then sell you the razor blades.
This morning, hundreds of Amazon Kindle owners awoke to discover that books by a certain famous author had mysteriously disappeared from their e-book readers. These were books that they had bought and paid for—thought they owned.
But no, apparently the publisher changed its mind about offering an electronic edition, and apparently Amazon, whose business lives and dies by publisher happiness, caved. It electronically deleted all books by this author from people’s Kindles and credited their accounts for the price.
The irony is that the books that were deleted were George Orwell's "1984" and "Animal Farm", two masterpieces about freedom and equality