I think the easier answer is that Verizon iPhones are strong but not earth shattering. All evidence so far supports that sales are lower than expected (best indicator: Apple has yet to do their typical "we sold a million in 48 hours" press release that has followed every other major release). It was important for Apple to get on more carriers and I am sure it will net another few billion, but my guess is the tech community overestimated how much pented up demand there was.
Yeah, I'm surprised people were so bullish on the VZW iPhone. Consumers have had 4 years to switch to AT&T and buy an iPhone. Why would the VZW iPhone change the market equilibrium in the short run?
I have said previously on HN that the Verizon iPhone was too little, too late, and that last Summer, Verizon's Android offerings became good enough for most of the consumers that wanted a smart phone on Verizon's network. Those that wanted an iPhone badly enough had plenty of opportunity to switch to AT&T; the remaining hold-outs -- those that hated AT&T passionately enough (or were in areas that it didn't serve) -- gave up waiting last year and found a good enough Android device.
I'd also argue that consumers are savvy enough to predict a new iPhone coming out later this year — after all, it has been on a yearly cycle since its launch.
They may be holding out for a new release rather than committing to a contract/service now.
I fall into both these examples. I had an iPhone and kept waiting around for either better reception or verizon iPhone. I finally gave up and bought the droid 2 last aug but it isn't as good as the iPhone. I qualify for another upgrade this aug which puts it right about the time iphone 5 comes out. I'll wait for 5 then dump droid and go back to iPhone.
I don't think it's about lack of pent up demand, it's that this actually doesn't offer the iPhone to most of Verizon's customers.
A lot of us will change, but that demand is going to stay pent up until our upgrade cycles stick around. The pricing just isn't right ($600 without an upgrade), whereas coming from AT&T $200 isn't that bad. Verizon still has many eggs waiting to hatch in its customer base.
I don't think lack of early sales reflect the lack of value of the phone, just the fact that people know they can wait a bit longer and get it for 1/3 the price.
An interesting question would be how many Android phones did they sell at Verizon over that same time period. If Android at Verizon sold neck and neck with Apple during this time period, that probably bodes less well for Apple. But if the iPhone is selling much better, that's a good sign, especially when the iPhone 5 comes out.