I honestly think the LTE part of the equation is what is messing everything up. LTE is still in its infancy and causing issues. And ICS did have to be slightly modified for the LTE application over the other applications, so that is probably throwing a wrench into the works. Look at the other LTE phone problems that have happened with Verizon. Throw a new operating system on top of it and the issue is compounded.
I agree its something with the phones software/hardware that's the issue. Every 4g phone released has had lte issues, so it doesn't make sense that its only network. Definitely something with the software/hardware of the nexus.
But as I mentioned before, the only other conclusion that can be drawn is that this was vzws plan all along, but with the bug reports out there that doesn't really hold much water.