It really remains to be seen if voice grade services could be supported by Wi-Max and then you have 911 service requirements. If you transport voice then at some point the regulators will get involved.
Hell, I'd just like something that would replace currently wireless coverage so that I could get contiguous coverage on my cell phone. Being able to have wireless internet throughout an entire market would be wiked cool too though. I would have a laptop with me at all times.
There's a modification to Linksys WiFi routers which sets up an impromptu telephone network between in-range routers. If Linksys just included and activated that as a feature, possibly promoting it thru WalMart et al, the "just happened" network would not be subject to regulation (like requiring 911 support).
It's a disruptive technology waiting to happen, providing national telephone & internet support for free (reliability not quite as assured, but then again compare Windows to Linux).