This article investigates the wireless industry in the United States and the Global System for Mobile Communications (GSM) and non-GSM revenues around the world. The real data available until 2003 suggests an “S” shaped diffusion might be in place globally and perhaps for the United States. We used a modified Bass diffusion model to compare to the real data and extended this model to forecast future data to 2020. We observed that the diffusion of wireless technology in the United States (WTUS) will stabilize in 2011 and that the saturation point will be reached around the year 2016. We also analyzed the global diffusion of GSM and non-GSM technologies. We show that the global revenues from GSM technologies may continue to increase until 2010 when the total market potential is predicted to be $600 to $800 billion and the switching cost is taken to be 0.1, 0.2, or 1. In another scenario, non-GSM revenues become greater than GSM revenues.