Two separate reports paint quite a picture of how the way Americans communicate has changed — with dramatic implications for how business communications will be done in the future, as well. One quarter of U.S. homes have given up their landlines and use only a cell phone, according to a new survey conducted by the National Center for Health Statistics, a part of the Centers for Disease Control and Prevention. At the same time, The New York Times reports that while almost 90 percent of households in the United States now have a cell phone, the growth in voice minutes used has stalled in favor of data communications.