Alright lets break this down
AT&T: Unlike Verizon, AT&T offers the most popular smartphones in the industry.
Sure you do have the iPhone but thats about the only smartphone that Verizon doesn't have, They carry blackberrys, android phones as well as palm and HTC... so yeah you have the exclusive iPhone... but for not much longer...
AT&T: Unlike Verizon, AT&T customers have access to more than 100,000 applications, more than with any other wireless company.
Yeah again iPhone... whoopty Fing do... if you were to take all these apps and remove all the duplicate apps that do the same thing, and then were to take the ones of the previous versions you would get about under 40k apps. They can't count blackberry, palm, HTC because they all can get the same apps from them on any network.
AT&T: Unlike Verizon, AT&T's 3G network lets wireless customers simultaneously talk and surf the web or do e-mail.
Maybe they could say that years ago but I think with any smartphone this task is easily done. So AT&T is dumb for reaching at this one.
AT&T: Unlike Verizon, AT&T has the nation's fastest 3G network.
Meh you might have one there but it's debateable.
So there you have it 2 of their given reasons are based on the iPhone. 3rd reason is just dumb and last one isn't true all the time.