They are running ads supporting the new Google "Droid", pointing out what they advertise as perceived flaws in the Iphone, along with the ads parodying the "there's an app for that" to try to say that they have better nationwide coverage than AT&T.
Some perceive this as an indication Verizon doesn't want Iphone. Others perceive it as a negotiation tactic.
In Canada, Iphone will soon be available on all 3 major carriers. Non-exclusivity has also arrived in the U.K. and China. If Verizon outright refused to come to terms for Iphone, I'd wager that it still ends up on T-mobile with AT&T as soon as AT&T's contract is up. Maybe Sprint, depending on their progress moving to "4G". Anyway, if any of that unfolds, Verizon customers might not be happy with their inability to choose the product when multiple carriers have it.
I think Verizon is posturing to get Apple to change their business model, i.e. get Apple to lower the iphone cost so Verizon doesn't have to offer a huge subsidy. The reality is, Apple is going to have to lower margin to increase market share in the PC and phone product areas.