The marketplace is easy to search?
"Here at El Reg we carefully put QR Codes on our Android app reviews, but in fact its easier to run the Android Marketplace and type a few letters of the application name. The same applies to shops and businesses; Google can find a business with surprising speed from the name, while snapping a QR Code can take a surprisingly long time."
I'm happy to agree that the Google search engine is impressively good at finding matches for business names, but I'm not convinced the same is true of the marketplace; it appears to have very loose matching rules and (as per Yell.com but unlike Google's search engine) presents the search results in a randomly shuffled order, so as to give all apps a fair chance.
TBH, I think NFC and QR codes are two separate systems and should be treated as such; you can't store a huge amount of data in a QR code (though you can link to it), but you can't access a NFC from ten meters away, neither can you print out NFC codes in a magazine nor email them to a friend.
I think the biggest problem is that there isn't a standard QR app for Android/iPhone; not only do you have to download one separately (e.g. Barcode Scanner) but it also limits the level of integration with the OS. Admittedly, most of them simply resolve into a URL which you can then launch in the browser, but I'm sure you could do more interesting stuff, such as the Augmented Reality stuff in the 3DS (e.g. have a new URL format such as augrel://this.is.where.you.download.the.data - your phone could then download the game/info associated with the QR and do it's funky stuff, such as overlaying street signs or cute fluffy bunnies)...