i think that IX was the best out of the three PS1 final fantasies. i can see them now remaking the original i, ii, and iii for the ds, but thats because the graphics are so antiquated. plus, you dont want a revival too soon. i think the only game that worked for was when they re-made the original resident evil for the gamecube. the concept of the original game was awesome ("survival horror") but the voice acting and controls and stuff were a little lacking. ff IX has a great story line that, in my opinion, doesn't warrant a prequel or sequel. the gameplay is great (again, IMO) and the graphics aren't too outdated yet. perhaps sometime in the future a remake will be in demmand. for the time being, i personally am content to replay the original on my PS1.
Many people, including myself, don't want a prequel or sequel. It's the remake that looks nice. Actually I enjoy playing the original FFIX on the ps1. Thing is that a remake might get previous FFIX-haters to get interested again, just for the fact that Square is remaking a FF game. So look at my other post above this one and check out the petition!