First I'll start by saying that I literally joined to comment on this matter, usually just a lurker.
In my opinion,
The first thing to remember when looking at all aspects of these rumors is that Apple is a business, and as a business they have one thing in mind, making money.
Those who think the iPhone isn't coming to Verizon at all aren't very smart. Verizon is the largest mobile service provider in the country. It is only logical to assume that the largest smart phone will be put on this carrier at the first available opportunity, which may very well be 2011.
I believe that AT&T's exclusivity is set to end this year. Based on have read it should have been at the beginning of 2010 but because of a deal on iPad pricing between Apple and AT&T the exclusivity of the iPhone was extended for a year. I assumed that to be common knowledge.
As for who will make the announcement and when. Yes Steve Jobs is known for being the center of the spot light on new products. However, a CDMA iPhone 4 is not a new product, it is simply a different chipset. As mentioned by others in this thread, Apple did not announce when the iPhone was moving to other carriers in other parts of the world, that job was left to the carriers themselves. I personally feel that it could be announced by Steve and Ivan together on the 6th or Apple could possibly hold their own PC later in the month, IMO there is no telling.
It makes sense also that Steve Jobs would want this announced along side/on the same day as Verizon's announcements of Android phones. The Android OS is obviously the iPhone's biggest competitor but let's be honest if a Verizon iPhone is announced the same day no one is going to be talking about Android phones. Why wouldn't Steve Jobs want to steal the spotlight from droid phones like that?
As for Apple not releasing an iPhone 4 on verzion just to turn around and release the iPhone 5. Since when has apple worried about whether people just got a product before the turn around and update it? This is how they make their money. They release something, improve it 6 months later and reap the benefits of people who have to have the newest thing. It makes perfect sense for Apple to make millions of dollars on the iPhone 4 from Verizon and then turn around and do it again 6 months later with the iPhone 5.
As for Apple not releasing a CDMA iPhone because it is a "old" technology. You have to remember that Verizon isn't the only phone carrier on CDMA globally. There is also India and China to supply with iPhones, and as a business you better believe Apple wants all the money it can get.
I think that about hits all the talking points I have seen here.