Analysts weigh in on the potential sales impact of a Verizon iPhone.

For those waiting for a Verizon iPhone, the wait may not be much longer. Citing a person familiar with Apple's plans "who isn't authorized to discuss them publicly," Bloomberg has been reporting that Apple will "probably" introduce a Verizon iPhone after next week's Consumer Electronics Show in Las Vegas. But what's interesting about the latest articles is that analysts are already predicting the number of AT&T customers who will defect to Verizon for its new iPhone.

The estimates range from 1 million to 6 million moving from AT&T to Verizon, though the bulk of sales of a potential Verizon iPhone would still come from current Verizon customers updating their existing phones.

The Bloomberg article quotes John Hodulik, an analyst at UBS AG in New York, who comes in "somewhere in the middle" with his projections, saying 2.3 million would switch from AT&T to pick up a Verizon iPhone. Hodulik expects AT&T would sell 8.8 million iPhones in 2011 (down from 15.6 million in 2010) and that Verizon would sell 13.3 million. Of those 13.3 million, 10 million would go to Verizon subscribers and the rest would come from other carriers.

If indeed Verizon introduces an iPhone later this month, there are still some unknowns that could affect sales. For instance, how much will service plans for a Verizon iPhone cost (typically, Verizon's plans cost more than those of rival carriers), and will the phone offer any new enhancements Also, despite a lot of AT&T customers being unhappy with that carrier's service, many will be weighing whether to hold out for an improved fifth-generation iPhone that will arrive in June and may support 4G data transmissions. Additionally, AT&T could offer incentives for customers to stick with the company. And finally, perhaps its service will improve as more folks defect to Verizon.

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