T-Mobile CEO John Legere’s trash talk doesn’t seem to have hurt AT&T’s standing among its customers. The latest survey from J.D. Power shows that AT&T has overtaken rival Verizon to have the highest customer service satisfaction rating among major carriers in the United States. What has to make this particularly sweet for AT&T executives is that J.D. Power ranked T-Mobile dead last, which should take some wind out of the upstart carrier’s sails the next time it claims that AT&T customers hate their carrier. The good news for T-Mobile, though, is that it could soon get an infusion of happy customers from the recently acquired MetroPCS, which ranks first among prepaid wireless carriers for customer service in J.D. Power’s survey.