Why should a current AT&T iPhone 4 customer break is contract, pay the ETF, spend another 199 (or more) for an iPhone 4 and the associated fees just to get what he already had.
I truly don't think Verizon was honestly expecting hoards of AT&T customers to drop their contracts and switch right away. Remember the first commercial that was aired for the Verizon iPhone? It was directed primarily toward current Verizon customers, and thanked them for their patience and for waiting for the iPhone on their network.
I'm sure that Verizon is expecting a certain amount of people to ditch AT&T when their contract comes up, but you can be sure that they know not everyone has the money to deal with their ETF.