First of all, there is no way a PS4 would be releasing in 2012 given they did not reveal one at this year's E3. I would not be surprised to see a reveal during the 2012 E3 event, but that would put its placement in late 2013 at the earliest.

As for FFVII, I think fan demand has gotten so ridiculous now that Square-Enix may actually reconsider it... I remember an interview a long while ago where Wada had said that, while there were "no plans" for a remake, it wasn't completely out of the question. I wish I had the source for that interview handy at the moment, but... in any case, I wouldn't hold your breath for a remake, but I know I certainly won't be surprised if it happens.

The PS4 could be a viable candidate, since the ones receiving overhauls are still the old SNES-generation titles... as we are three generations removed from those, it may make sense to finally revamp the PSX titles once we are three generations beyond their releases.