The Süddeutsche Zeitung reported that as many as 5000 Vodafone Germany customers have bought iPhones. That's 5000 customers who could have otherwise purchased a Vodafone Qbowl - which was released in Germany the same day as the iPhone - and Vodafone is NOT happy about that. Vodafone has not done this in the interest of the customer, they've done this to stem the tide of customers defecting to T-Mobile. If you look at the plan that they offer for the Qbowl, the terms are even worse than T-Mobile's plans for the iPhone, plus the Qbowl is exclusive to Vodafone. Problem is: nobody cares about the Qbowl.
This is a classic example of sour grapes from a company who missed out on a good thing and are regretting it.
It does, however, raise a very interesting question: what happens when your 2 year contract runs out, and you want to switch carriers? You have to resell your iPhone to a T-Mobile user, or you're screwed. This is the only reason I hope they are able to get T-Mobile to take the SIM Lock off of the iPhone.