Amazon actually upgrades their software a lot. The most recent update for the second generation Kindle added folders, native PDF support, PDF pan and zoom, larger font sizes, password protection, facebook/twitter links, and password protection. They don't simply just "dump a new reader out there." I've always gotten the impression that B&N is just playing catch up, trying to offer a lot of the same features that Amazon does. (To be fair, though, Amazon is doing the same thing. They're copying B&N's LendMe feature for lending books.)