Just 12 years ago, in writing a research memorandum on the future of global telecommunications, I noted the oft-quoted estimate that roughly half of the planet's population had never made a phone call in their lives. Fast forward to today, and best estimates are that 55 percent of the planet owns a mobile telephone. Factor in that the highest rates of growth are occurring among the poorest and most disconnected populations, where communal use of cells is the norm, and it seems likely that this pool of phone-call virgins has been cut in half -- or better.