I didn't think that a simple post on multimedia functionality and QR codes would generate so much chatter.
General consensus seems to say that it would be an interesting gimmick, but probably wouldn't have a whole lot of functional value. TinyURLs might serve the same purpose just as easily, a quick footnote at the bottom of the page with a web address that links to a descriptive video of the concept under discussion.
A few people have pointed out that QR codes have a time and a place, they tend to be best on street advertising and billboards where they can be used to direct an observer to a specific part of the web when they are on the move and unable to write things down. In a book, the reader has the time to write something down like a TinyURL, and such a thing is less intrusive as a text footnote. If the game design were cyberpunk inspired, then the imagery of a QR code might be more fitting...it's not necessarily great for a post apocalyptic work.
I still think there is value in generating up a few videos to clarify play concepts. Different people learn by different methods; so having a wall of text, a comic series of still images and a collection of videos improves the ability of various users to connect with the intended play experience. It also helps to explain where the rules lie, players can always work outside the intended rules and understand how they are modifying the play experience...but they need to know where the rules are, so that they know where they are deviating. A lot of people blame the game without playing the game in the way it is actually intended.