The only con I can thnk of, and to me it's a huge one but NOT a deal breaker is, Verizon's pitiful IN STORE customer service. I've experienced this in Binghamton, Syracuse, Albany and ELmira, so I know it's not just my local stores. It just takes FOREVER to get service there as the waits are unbearable.
WIth AT&T with me, at least locally, with maybe on average 75% of the customers in the store, the wait times are MUCH less.
That said, VZW gets the iPhone and I switch in a hearbeat olnly because of the better coverage. It's not horrible in my area, but a tad weak in my apartment vs VZW, and some areas I frequent locally MUCH worse than ATT and even some zero bars areas.
Mike