I'm not too concerned with updated graphics; I wish more classic RPGs would get a decent porting to the DS. The updated FF3 was pretty sweet, but I don't think IV really needs updated graphics. I'm sure it will be nice, but for, say, FFVI, updated graphics would ruin the charm of the original.
SE understands that remaking FF games will make them a ton of money, especially highly-overrated FF7. If FF7 can be remade, it will be, but not before SE has sapped the money out of the earlier games. I'm sure FF7 might be a bit more sticky due to Sony, but Hiromichi Tanaka said it would be possible not only to make one, but that they're sure it would sell well.
They've also had some interest about putting the games up on the Wii Virtual Console, though I haven't heard anything about that in a bit.
The one good thing about SE's realization is that they'll continue to reproduce older games, which were generally much better than the current generation of SE titles.
Personally, I'd rather see Chrono Trigger on the DS than any FF game.