The best solution for the USA is the implementation of 802.16/802.20 WiMAX long-range wireless networking technology. Unlike WiFi, WiMAX can cover thousands of users on a single antenna array literally up to line of sight; this means you only need a relatively small number of antennas to cover a whole metropolitan area, and it also means you can get broadband Internet out to rural communities by placing WiMAX antenna towers on mountainsides, hilltops, the top of grain silos, or small standalone towers on flat areas. Indeed, we can "piggyback" on top of current cellphones towers as one way to get WiMAX widely available. Because of WiMAX's potential speed as high as 45 megabits per second bidirectional, this also means that same broadband Internet connection can be used to set up local telephone service using VoIP.
You don't have to wait for HypeMax. WiFi has already been doing the job and is less expensive. Even with that is hard for WISPs to make financially. WiMax gear will be very expensive making it hard for current and new WISPs to justify the cost. But otherwise yes you are right. Using Wireless Broadband for the last mile in rural areas is the cheapest alternative compared to a Fiber/Copper solution.