As soon as I saw the first mid air shotgun refresh I was hoping for chains of them and I was not disappointed. Small thing that would add to the user feel would be to have some indicator that you've still got an extra jump left. Yeah, you should know that as you just grabbed it, but having something appear on your screen when you collect something and disappear when you use it has a certain appeal.
Cool graphics, fun game - could see this becoming a very Super Meat Boy-ish game.