The problem with the radio spectrum is that it's a natural phenomenon -- the bandwidth available is the bandwidth available, and you can't simply create more of it. On the other hand you could free up a ton of spectrum simply by getting rid of the spectrum allocated to broadcast TV.
I don't see this happening, at least not any time soon. However, I fully expect the chants will grow louder, and more frequent, especially from the iPhone loving, Twitter and Facebook enslaved digerati who see unlimited wireless broadband as both holy grail and God-given right.
They argue, and reasonably so, that over 90% of the population already avails itself to cable and satellite services anyway, leaving less than 10% who use over the air (OTA) broadcast. One problem with that approach is that it understates actual OTA usage, perhaps by a fair bit, though it's true the number of homes that are exclusively relying on OTA is estimated at less than 10%.
Last Sunday's New York Times covers the issues with the limited wireless spectrum and proposes a way to free up the broadcast bandwidth:
Say there are 10 million households that still get their television over the air, including those that can’t afford cable or satellite and some that generally just don’t care for what’s on TV. (Yes, there are people who don’t like “American Idol.”) But about 99 percent of these households have cable running near their homes, and virtually all the others, in rural areas, could be reached by satellite services. The F.C.C. could require cable and satellite providers to offer a low-cost service that carries only local channels, and to give vouchers for connecting to that service to any households that haven’t subscribed to cable or satellite for, say, two years.