And it took until the end of the N64's life just to fit any FMVs into a cart. Now the DS is already quadruple the size, with larger sizes likely coming (doubling that, a DS cart would be nearly as large as a CD-ROM). So the voice acting in FFIV looks to be pretty feasible.
A flashy-first game is awesome when it comes out. A great-first game is awesome forever.
Plus, just for the hell of it: Kelly Brook at the 2008 BAFTAs