I would imagine they would say that if upgrading from 3G to to 4G, in fact I'm almost sure of it. However, there's a good chance that they will allow people who buy LTE phones now on an unlimited plan to upgrade their devices in the future while keeping that plan. Of course they don't have to, but that seems to be par for the course. For instance, people who had an original iPhone on ATT can still upgrade to a iPhone 4 and keep their unlimited data. If VZW feels that their LTE network would be seriously threatened by the comparatively small number of users who still have unlimited 4G 2 years from now when they're due for an upgrade, then yeah, they'll have to go tiered if they want contract pricing. But its likely that they'll just let you upgrade no problem, rather than risk driving customers away. Knowing Verizon, its highly unlikely that their network won't be able to handle it by then.