According to this Joystiq report, Nintendo’s confirmed that “Japanese freeware cult-classic” Cave Story is to release in the US on WiiWare this year. From the piece:
But it’s not just a straight port, oh no. The indie Metroidvania title will have “new, exclusive content and features created only for the WiiWare version.” No word on what those are, what Cave Story will cost or, really, when “this holiday season” it’ll be available to play. But, hey, if you’ve got a “computer” at home, you can play it today. Without waiting. Or paying “money.”
So there we are. More through the link.