Nobody yet knows which U.S. carrier will get the right to sell Apple's iPhone next, in 2011. There is logic for, and against, it being Verizon. At the moment some reports suggest Apple and Verizon are talking, but are not yet agreed on terms and conditions.
That makes sense. Verizon has been doing quite well with HTC devices lots of people do believe is the family of devices most similar to the iPhone. For that reason, Verizon might not feel it has to give quite so much to Apple to acquire rights to sell the iPhone.
Apple, on the other hand, has to weigh the advantages of a much-bigger base of customers Verizon would bring, compared to either Sprint or T-Mobile USA. Also, given component shortages at the moment, Verizon and Apple have to be weighing possible impact on device profit margins as well as ability to meet demand.
Verizon might not be willing to give Apple the margins it wants. And Verizon has to estimate a possible shift in demand from HTC devices to iPhones that result in no net gain in subscribers.
It is a fair guess iPhones will be available on some network other than AT&T's, in 2011. It will an important decision no matter which network it proves to be.