"And Verizon punters are going to be extremely less likely to buy an iPhone in Q1 if they know for sure a snazzier model will be out in June."
If that was the case, would they have not jumped ship and brought the current one, thinking that a CDMA version is not going to appear.
If someone is on a CDMA network, they are unlikely to be put off upgrading their phone because a new GSM phone is on the way.
Unless you are trying to insinuate that the iPhone 5 (in June 2011) will be both GSM and CDMA???