Just to let you know, when details confirming or denying these theories comes up, I'll label them so. It'll be fun to look back.
From Wario's profile on the official site:
"The flatulence you saw in the movie is a fantastic move we're tentatively calling the Wario Waft. The more time passes, the more Wario's gas builds up..."
-If the move is nearly as 'fantastic' in-game as it was in the trailer, this statement could actually foretell the mechanics for the super move. Having to 'build up' your attack before grabbing the icon and unleashing it would be an interesting element.