You didn't see Microsoft take its toys and go home when Apple started their negative 'mac vs pc' ads. They stepped up their game and hit back with the price and flexibility advantage of PCs. AT&T, if they had any justification to say that Verizon is being deceptive, needs to just step up and hit back with whatever it is that they are better at. At the moment, the only thing going for them is their iPhone; their 3G network sucks, their voice network sucks, and their prices aren't competitive enough to differentiate themselves.
Go ahead, AT&T, ride the iPhone craze til it comes to a complete stop; other networks and handset makers are busy innovating you into oblivion.