Originally Posted by cassidym
But isn't BN going to switch to ePub. And, if so, will their books then work on the Sony?
Yes. Initially for the Nook only, but presumably ePub will be on available for all B&N supported platforms eventually. However, B&N will be using "social DRM" (credit card name and number) on their ePubs. This will be available via mobile Adobe Digital Editions to all licensees (i.e. device vendors) next year, but Sony does not typically update ADE very often (if at all) on their devices and they are not obligated to implement B&N's DRM. So the bottom line is that B&N DRMed ePubs will be Nook-only for now and perhaps limited to a few device types forever.