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.