When I asked a VZ saleswoman, she specified that a non US SIM won't be honored by the iPhone and that I would be encurring into the roaming provisions of the contract.
But the cloud was lined in faux gold. I could save money by pre-enrolling in their global package at an affordable $5 per megabyte.
Oh yeah. If you have bad credit or no credit, they will require a $400 deposit.
This should be a surprise to no one.