I love their games so this is great news. If it's for Wii U, this clearly means they're not dropping the system any time soon. I could see it very likely being for their next handheld, or a cross-system title for the handheld AND Wii U could be happening... and is almost implied.
I'd love to see the best elements of Galaxy(new theme, innovation, presentation, grand scale), 64(ground breaking with exploration) and 3DW(tight controls, classic power-ups and damage system, multiplayer) brought together in a semi-open world experience. Add to that some new themes for levels and online multiplayer and we could see a masterpiece. I'd love so see some Mario Kart locations as worlds too. Can you imagine exploring the city in the background of MK8 Rainbow Road??









