I Googled some of the key words in an effort to find more pictures and found that over the last 10 years or so these giant nest have been appearing with increasing regularity.
They first thought that they were the product of mild winters not killing off the colony, but now believe that it's a situation where there are multiple queens all laying. Some of the scientists interviewed in some of the news reports said they expected to see this more and more as this certain strain of yellow jacket became more common.
I found it odd that in 100% of the stories the person who owned the land/barn/car/mobile home where the nest was said that be had plans to kill the wasps in the immediate future. I think if I had something like that, I'd feed it....and keep it warm over the winter....and see how big it could get.