Not that I don't dig this whole augmented reality thing, by the way. I think that stuff is awesome, and it's definitely part of the process, but we should not consider it an end point. It's probably always going to be limited in some sense. As a concept, it ultimately seems backwards to have a machine that tells you about the environment rather than having the environment tell you.
My personal favorite is this movie by Microsoft that shows how damn cool the future will be once we build monitors into EVERYTHING.
http://www.youtube.com/watch?v=8Ff7SzP4gfg