The following is from NetWitsThinkTank:

This phenomenon is not just occurring in the US – According to a report by International Telecommunications Union (ITU) mobile subscription growth was strong in developing countries (which have 3.8 billion subscriptions), from 53 per cent of total mobile subscriptions at the end of 2005 to an estimated 73 per cent at the end of 2010. AMD is predicting that, by 2015, 50% of the world will have an Internet connection and Phone Count predicts that by 2012 there will be as many connected mobile phones as there are people in the world.