Less than three months ago, most analysts expected Verizon to snatch up to 6 million iPhone users from at&t this year, a loss of customers that would cost at&t up to $6 billion in 2011 alone. But according to at&t itself, this ‘mass exodus’ of iPhone users is not happening. In an interview published in the Wall Street Journal earlier today, at&t CEO Ralph de la Vega mentioned that at&t hasn’t seen any surprises, and according to him, “everything is pretty much within our expectations.” While at&t’s 15 million iPhone 4 users were not expected to make the switch, as most of them signed up for a new two-year contract when the iPhone 4 launched in June 2010, analysts expected Verizon to tap into the pool of 8 million at&t iPhone users who decided not to upgrade to the iPhone 4. Some of them made the move, but as of today, only 150,000 users allegedly switched to Verizon. The launch of the iPhone 5 later this year could drastically change the situation though, as users willing to upgrade their phone will have the choice between Verizon and at&t from day 1, since Apple will most likely release a device compatible with both Verizon and at&t’s networks, just like the iPad 2. Meanwhile, at&t is working hard at improving its network, now that its biggest competitor offers both iPhone and iPad. For instance, at&t made significant investments to upgrade its equipment throughout 2010, especially in densely populated areas, such as New-York and San Francisco.