AT&T today announced its 4Q 2013 earnings, revealing the company added 1.2 million postpaid smartphones to its network (both upgrades and new subscribers) and gained 809,000 new subscribers, with 566,000 being postpaid customers with a contract. It is unclear how many of AT&T's new customers were choosing iPhones, however, as AT&T, like Verizon, no longer reports quarterly iPhone activations or...