I hope you get it sometime soon after it comes out... Simply because after hearing Metal Mario is playable, I've felt like shoving my face right near someone else's and saying in an annoying tone: "Did you know Metal Mario is playable in Mario Kart 7?"
Metal Mario just doesn't appear often, not even as often as Shy Guy, so that's why I'm excited about Metal Mario being playable. But on the other hand, I agree - Shy Guy should be in it. Makes perfect sense to me. Let's hope he makes it. I'm actually hoping for Diddy Kong, Shy Guy and Paratroopa. Doubts about Para, though... But if he IS in the game, that'll give me quite a good choice besides regulars!