We may not, officially, know about any of Nintendo's post Wii Fit releases for 2008—the company is keeping quiet, presumably until E3—but the ESRB has rated ASH: Archaic Sealed Heat for release on the Nintendo DS, all but assuring a North American localisation this year. Nintendo of America hasn't announced that the Mistwalker developed role-playing game will come stateside, but that E10+ rating is a very good indication that it will.
The Hironobu Sakaguchi produced RPG was released in Japan in October of 2007, doing well with critics, but underperforming in the sales department. In its debut week, only 50,000 copies were sold to Japanese consumers, with ASH falling off the charts soon after. Here's hoping that Sakaguchi and crew have more luck in the West.