Here (computerandvideogames.com) and here (pcgameworld.com) are interviews with the lead designer for the game. He talks about some of the new content (which will eventually be available for download via X-Box live, so fret not, X-boxers) and other aspects of the game.
Also, here (pc.ign.com) and here (gamespot.com) are some hands-on previews. They don't say much more than that the game will ship something this November. (I *know* I saw it say somewhere that the date was 11/18, but I can't find that now for the life of me...)
Figured I'd try and beat KJames199 to the punch on this one. The inevitable announcement is here. To compete with Xbox Live Arcade and the PS Network, the Wii will now offer original downloadable titles to complement the Virtual Console. IGN: