In today's The New York Times, the city of New Orleans ran a full-page advertisement to promote the city's food, music and events, as well as travel deals. The ad features a Microsoft Tag, which is branded with the same fleur-de-lis icon that is also used in the campaign logo ("It's New Orleans - You're different here.").
For readers who may have never seen a Microsoft Tag before, let alone a 2D barcode, all of this is new to them, so the descriptive text which accompanies a code really needs to be explicit and very much step-by-step. To accomplish this is a limited amount of space is, of course, the great challenge, but advertisers need to fully and properly explain 2D barcodes if they wish to have fast and widespread acceptance of the technology, let alone a decent ad response/scan rate.
Also, from a more strategic sense, what about all of those people who do not have the ability to scan the Tag, because they do not have a smart phone (still the majority of mobile phone users). There should be a shortened URL next to/near the Tag so that non-smart phone users can access the same information and deals.