Interesting......I live about 35 minutes from there and my 2008 Denali was built there. I always wanted to go on a tour, but was too late when closing was announced. The only thing left there now is a flat lot with an electrical service yard.
It doesn't surprise me that GM razed it.....the stories I've heard over the years of corruption, theft, boozing, etc makes me sometimes wonder how anything turned out as well as it did.
If you find out how on yours, I'd be curious to know as well.