@contrex,
I get what the "be+ing" is referring to now. I never knew that was the polite way to ask a simple question.
I would probably just ask something like: "What the hell are ya gunna be doin on Saturday?," my own damn self.
I guess a cheese-eater might take "offense" at that and somehow consider it to be "nosy."
But I don't have much truck with cheese-eaters, so I really wouldn't know.