Yeah that's something that does suck about Verizon. Though during the press conference Verizon said how when they get the 4G network up can running this year, than the data/voice feature will be available, not to mention video chatting over 4G.
Verizon's assumed term "4G" or really LTE is already available but only as a hookup to your laptop for mobile broadband. The phones that can actually use Verizon's "4G" are supposed to come out this year, but I doubt it will be the iphone. I was hoping for LTE iphone but Apple likes to control their product line, and they don't want users to notice a difference in the same product just because it's running on different carriers. So because things are kept leveled, basically you're not going to see a "4G" iphone until AT&T implements 4G as well... and who knows when that will be, 2012?
Also, if existing AT&T iphone users want to switch over to Verizon they can keep the software by backing it up, but because of Verizon's CDMA network, they'll have to buy a new phone. Still feels a little awkward on the timing but overall a win for Verizon imo.