There's too many legacy uses, too much investment and too much utility to wave a magic wand and declare ALL radio spectrum "open spectrum". There's no surer way to eliminate the possibility of open spectrum actually being implemented than to tie it to the proposition that the entire existing allocation scheme must be scrapped. I wish some people understood that. There's value in imagining and discussing "what if?" scenarios, but when all is said and done, it's important to be able to separate fantasy from reality.

The Upper 700 Mhz band is the logical place to implement open spectrum in the U.S. -- at least initially. There are vast areas of the country where it's virtually unused. Once the open spectrum model has proven itself, other spectrum users may voluntarily want to lobby for the opening of their own bands and join the commons.

One more thought: The idea that "we're not far along enough to determine now what we need -- we should try both for ten years and then revise it all," is just... bad. Look at all the damage that's been done in just the 7 years since the Telecommunications Act of 1996 was passed. Bad laws have tangible effects that don't always go away when the law gets fixed.