On his blog, Jeff Pulver questions the concept of fixed-mobile convergence, suggesting that cellular networks don't have anything to fear from Wi-Fi or WiMAX.

"I'm amazed how often people just assume that the widespread availability of public Wi-Fi hotspots means that therefore Wi-Fi VoIP is a done deal," Pulver writes. "While there is no doubt in my mind the advent of public Wi-Fi means that in the future consumers will have a choice of whether to pay for data services on their mobile phones or choose to take advantage of Wi-Fi hotspots to use PCs, PDAs and other IP supported devices, who says that people will be using these devices as a replacement /substitute for their mobile phones?"

Seven years from now, Pulver asks, will there be more people speaking over mobile networks or on Wi-Fi/WiMAX networks?

I'd suggest the answer is both. Mobile networks and WiMAX networks will become one -- maybe not within seven years, but eventually, omnipresent wireless broadband for voice, video and data is just plain inevitable.