Makes no sense to me...
One thing that makes absolutely no sense to me about this though is that Apple cannot produce them quickly enough as it is. Right now, there is a 3 week wait time for the iPhone 4 in the US and Canadian Apple Stores. And Apple has rolled it out in only a handful of countries.
If you assume that manufacturing capacity is the main production constraint - rather than the availability of the right kind of GSM radios -, then what exactly does a CDMA iPhone mean to Apple's bottom line? I assume the profit per phone would be more or less the same, but they would have twice as many different models to produce... on the same production lines, I assume. Maybe I am looking at it with too short a perspective, but I really don't think Apple needs a CDMA phone right now. They can sell tens of millions of the GSM iPhone 4 this year, and they will sell them as quickly as they can build them for the foreseeable future. A CDMA iPhone would just make the wait times longer, I think. It would increase demand, but if supply can't go up, it doesn't mean anything.
If they can't sell more due to manufacturing capacity constraints, why would they do it? It would add to consumer confusion and a bunch of uninformed customers would buy the wrong kind, or buy one and then complain that they can't switch from Verizon to AT&T or the other way around. It'd be rather messy, I think. Well, messy by Apple's standards anyway.
I'm not saying it won't happen. I'm just saying that it seems more logical for Apple to wait for LTE before introducing a single iPhone model that will work - if I understand this right - on both GSM and CDMA networks. The iPhone 5 next summer? The 6 in summer 2012? I don't know. I guess it mostly depends on when the networks are ready.