USPTO strikes again.
Rather than going around suing everybody, I suspect that Amazon is going to try to leverage this development into controlling distribution on non-Kindle devices. As I've said in previous threads, Amazon isn't making money off of selling the Kindles--they're margins lie in selling the content. Rather than seeing this news as a blow to eDGe users, I think that it has the potential to improve the functionality of the device if the upshot is that a "Kindle for eDGe" that allows Amazon ebook purchases to be displayed on the eInk comes about.
I can't imagine that enTourage (or the venture capitalists behind it) are all that pleased with this development, as I'm sure that they were hoping to generate some revenue from selling content. But they have a chance to make this into an opportunity if they can somehow negotiate acceptable terms with Amazon. They may lose a good chunk of the revenue stream generated by content sales by partnering with Amazon; however, they probably broaden the appeal of the eDGe by allowing access to a much larger (and often better priced) eBook store than what enTourage (or others like Sony) currently have.