There's quite a bit of tension between AT&T and T-Mobile. America's two largest GSM carriers have gone after each other in ads, on Twitter, and in court. Now AT&T is willing to
bribe pay customers who switch to the carrier from T-Mobile up to $450 in credit per line.
Starting today, customers who take advantage of this limited-time offer can receive a promotional card worth up to $250 by trading in a smartphone.