It will be interesting to see how VZW handles this situation if indeed there is a shortage of a part or parts for the GNex.
I was there for the DInc shortage and this one can play out very differently. The main difference being that for the DInc, it was the only kick ass android phone out and no other phone being even close to being released with similar specs or better. If I'm not wrong, the next phones to come out were the EVO and DX but that didn't happen for months later.
With the GNex, there are already 2 other phones that can be substitutes to people that are not willing to play the waiting game. And even if one decides to wait, who knows how many new models will come out by the time they are able to fulfill the shortage given the rate of new android phones coming out nowadays.