The Next Betamax?

Josh Marshall engages in a second round of Kindle-blogging: much as like the Kindle technology, it's worrisome that one company -- i.e., Amazon -- could develop such a stranglehold on books. If I buy lots of books over the next few years for Kindle and someone else devises a better mouse trap, is my book collection held hostage to Kindle and Amazon? I'd figure probably so. Some universal or quasi-universal standards like DVDs and CDs would be nice.