A 2D code can say a thousand words.
Two of these codes link to a website I chose. Can you tell what codes they are, who provided them, and how to get to that site?
These are only a few of the many 2D codes available today.
Two of the codes are easy to recognize, but can you identify the others?
In order for physical world connection to get adopted, there will have to be a "standard" code or scanning application that can read ALL 2D codes. This will be done by a software application, or in a universal database (won't be a direct connect function).
Barcodes are easy for a consumer to recognize and are "owned" by a corporation, but getting a camera phone to resolve them isn't.
Until camera phones can resolve a 1D code (barcode), 2D codes will be the physical world hyperlink of choice for both corporations AND consumers. Both consumers and corporations can create them on their own.
Here's the tradeoff for a mobile marketer and brand, do you want a direct connection with a limited number of codes, or do you want as many phones as possible to interact with your ad?
When the service providers choose their physical world scanning platform(s), they should keep in mind ALL of the abilities and limits from each 2D code supplier.