In Miles Buzz, a lot of postings ask for a decision between different programs, credit cards, Airlines, other offers, preferences, etc.

Most use the word "What" to start the question. "What credit card . . ." What program . . . "

I think it should be "Which". Since we are asking for a choice of several discrete programs, or airlines, or offers, "Which" makes more sense to me.

Which grammarians out there have opinions? What are your opinions?