So as it turns out, the company had an expiration date.
The stories I've seen made this out to be a combination of recessionary impact (snack cakes are not a high-priority item on a food budget: they supposedly lost over three hundred million last year) and at least two affiliated unions striking on them. Delivery was willing to take a pay cut, baking wasn't -- and so Hostess surrendered. They claim not to be making any money and they'd rather not lose it faster than they currently are: last one out, run your fingers along the inside of the wrapper to get the final bits. They'll keep their outlets stores open for a few days until the shelves are empty, but as of now, they consider themselves finished.
Stock up while you still can. It's not as if you have to worry about the stuff going bad.
The brands should survive: companies who don't have to rely on just those products might be happy to add those names to their portfolio. But expect a gap of a few months or more.