Amir Rozenberg from ConnexTo wrote a very good article on mobile codes standardization. As myself, he thinks every 2dbarcode reader should support one or both ubiquitous standard symbologies (QR Code, Datamatrix). But read for yourself:

Ubiquitous standard symbologies support with optional proprietary codes: Agree that the industry needs a standard that every code reader will support. Those codes should be QR, DM or both. No point in arguing the code formats issue. All vendors that want to be considered need to support standard codes, and can add support for more codes, like their own proprietary format and maybe others. Operators and brands can then choose the solutions they prefer. Consumers will have the ability to decode the codes and use them regardless of the code reader they are using

I would like to add, that the ISO standard codes must be readable in their URL form. As long as standard codes can only be used in shortcode form, they are not decodable by any reader who supports them. Shortcodes have their value, but it should be up to the client to choose between openess - meaning a code that can be read by several readers - or restrictedness to one reader.

See also:
Open Letter to the Mobile Codes Consortium – MC2
First notes for yet another barcode manifesto