I actually stopped in to a VZW store over lunch just to get a feel for the size of the Galaxy Nexus as I've never really played with one. They didn't have anything in the store even mentioning the GSIII.
I didn't bother asking any of the workers.
Unfortunately, all the GN phones they had out all had cheap protective cases on them so I couldn't even get a good feel for the GN.
That said, I'm down for the GSIII when it ships.
-Suntan