T-Mobile USA tops other top U.S. wireless carriers in providing overall customer care during the first half of this year. AT&T ranked second with a score of 757, followed by Verizon Wireless which came in just below the average level. Sprint Nextel ranked last among the top four carriers in the study with a ranking of 734. The report card is based on how well wireless carriers service their customers via telephone calls to a live representative or automated system, through visits to a retail location or on the Web.”]