WiFi and VOIP
Q. Will WiFi clouds and VOIP replace cellular?
A. No. Both technologies will co-exist and co-evolve over the years. Cellular radio's hallmark is mobility, especially over great distances. WiFi works best while stationary. The call you make over the net at Starbucks, while downloading some tunes, won't remain connected when you step to your car and drive away, even with a city wide WiFi cloud. It certainly won't stay connected at 60 m.p.h. while you drive to your next espresso. Cellular radio (internal link) can hold a voice call together in that circumstance, usually, your WiFi connection can not. And your WiFi enabled downloading will certainly stop or slow to a crawl as you go mobile. As speed increases bandwidth decreases, to the point it's no longer useful. Await developments!