Engadget reports that press shots for the Verizon iPhone show modifications to the antenna design for the new device. Notice the iPhone below has four notches in the metal band that surrounds the phone.
The Verizon iPhone uses a CDMA radio as opposed to GSM so its possible that the alteration may only be related to that change; however, it only makes sense that Apple would try to improve the antenna performance after Antennagate.
If this design had fixed the Antennagate problem, then Apple would've applied it to AT&T version long time ago instead of producing more iphones with the current design. I think, not having the data and voice at the same time is a bigger problem than the Antennagate issue.
The so-called "Antennagate" controversy stemmed from having the antenna in very close proximity to the hand. Obviously, this phone uses the same design. There's no thick coating or any other sort of change. Tim Cook also explicitly said they did the minimum design changes needed to accommodate CDMA and nothing more. No need to imply anything else without any information to back it up.