Yeah, the DS has been expanding a lot lately. Thing is, developers never take advantage of it. But I'm pretty sure FFIV takes a lot more room than FFIII, so I don't see why they couldn't do FFVII (original graphics though). I doubt it, though, it FFVII is like, the start of Sony's dominion over the Final Fantasy franchise. Every other mainstream Final Fantasy has been on either Playstation 1 or 2 after 7. (XI doesn't count, you MMO O_O)
FFVII on Wii??? NEVER. Go away. Let the Wii stick with, I dunno, the Tales of series.
The Ds got a FFXII sequel