As of right now Verizon is not even looking at a LTE phone and it takes some time to approve a phone. Their (verizon's) reasoning behind it is simple they are reconfiguring their network completely, if they release a phone to work on a unproven network and it does not work as intended (a very real possibility) they will take a huge hit. So they have made the decision to only release LTE for network cards so the bugs can be worked out.
LTE is not an upgrade it is a new network that to date no one has working correctly.
Metro PCS will be the first one out with LTE and they will launch with a handset, they are willing to roll the dice that they can get it to work. If they fail it will be bad but if it works they get a big boost. So the rewards out weight the risk for them not so for Verizon.
