I don't think gestures that imitate what the character does on the screen are a good idea in a 2d side-scroller. They can help immersion in 3d, and especially 1st person, but in 2d they'd just be confusing.
One of the things developers have to learn on the Wii is when to use the many unique features of the wiimote, and when to stay with the basics. Stuff like "zomg, wave it around like a lightsaber!!1" and "zomg, swing it like a whip!!1" sounds kinda questionable to me. =/







