contracts and DRM have the power to lock readers and writers into legally unbreakable shackles. There's no such thing as a proprietary book. There's no such thing as a license agreement necessary to read a book. Books are governed by a social contract that is older than publishing, older even than printing. The recent innovation of copyright in books recognizes the ancient compact between readers and writers, and protects your rights to own your books, to loan them, to give them away, to resell them, to read them in any nation, in any circumstance. A publisher or bookseller can't force you to buy Ikea sofas to sit upon while you read your books.
But Amazon can force you to buy Kindles (and Amazon-approved devices) to read your Kindle books on and listen to your Audible audiobooks on.
My main message to fanboys is this: it's too early to draw any conclusions. Apple hasn't given the thing to any reviewers yet, there are no iPad-only apps yet (there will be), the e-bookstore hasn't gone online yet, and so on. So hyperventilating is not yet the appropriate reaction.
At the same time, the bashers should be careful, too. As we enter Phase 2, remember how silly you all looked when you all predicted the iPhone's demise in that period before it went on sale.
Like the iPhone, the iPad is really a vessel, a tool, a 1.5-pound sack of potential. It may become many things. It may change an industry or two, or it may not. It may introduce a new category — something between phone and laptop — or it may not. And anyone who claims to know what will happen will wind up looking like a fool.