Beyond my personal reminiscing, the real point is don't confuse the potential of a technology with the potential of any specific implementation. A number of other comments have given examples that seem on their face to be more compelling than what Google is doing, but this is a common enough point of confusion that I thought it deserved to be called out specifically. None of this is to say that 2D bar codes definitely will be successful — only that Google's place on one side of the Spinal Tap quote above does not prevent someone else from being on the other side. :-)

BTW, I was originally a skeptic of 2D barcodes myself, but turned to be more of an optimist on the technology about a year ago (see here for why: http://blogs.msdn.com/johnmullinax/archive/2007… ).