I think connecting the real world with the Internet on a mobile device is going to be another little quantum leap into the future. The technology is all there (to the best of my knowledge): it's all about integration and economically feasible deployment now. The biggest pitfall I see is the mobile operators walling this stuff off, as they tend to, because they want a bigger piece of the pie, and thereby inhibiting innovation.
(Well, when I say the technology is all there - the one big chunk that is not there in hardware is GPS. Didn't I read a couple of years back that Nokia was going to include GPS in a significant chunk of their cell phones? Whatever happened to that? Luckily some people seem to be coming up with other ways of determining location - by triangulating signal strength from nearby cell phone towers for instance.)