While everyone has been (rightfully) talking about Mario, I think the real star of this will end up being Pokemon. I would reckon that Pokemon has more cultural power than Mario does. There's been many movies, a decade's worth of TV shows, and a hugely successful trading card game. It has gone downhill from its peak, but I think there's a lot more nostalgia towards Pikachu than Mario or Luigi. The upcoming generation (20-somethings) look at Pokemon the same way that the prior generation looked at... well, I can't think of a great example. But, Pokemon already has a huge following.
Plus, merch. Look at how much merch is out there and how much there was at Peak Pokemon. The entire series lends itself to merchandising to a much greater extent than anything in the Mario franchise.