Earlier today we announced that a 4.2.2 build for the Verizon Galaxy Nexus had leaked directly from Google servers! In order to flash said build you would have to flash back to stock whether that be by flashing a stock image manually through adb or by using one of the various toolkits. It can be an arduous process to flash back to stock then flash the OTA update. Mwalt had pulled the radios and made those flashable over your current rom.
P3Droid of TeamBlackHat has thrown together on of his famous All In One updaters for the Verizon Galaxy Nexus which will allow you to flash 4.2.2 over any custom Rom or build without the need to flash all the way back to 4.1.1 JRO03O. This makes everything nice and easy! This has only been tested in TWRP. If you are daring you could try in CWMR, but I wouldn't unless you make a nandroid first.
Grab the AIOUpdater.zip here