Remember how Square trolled us with that Final Fantasy VII for PS4 announcement that turned out to be just a port of the PC version with trophies?
...we're going to get an actual announcement that they're remaking FFVII from the ground up. I don't know if they'll have anything to show, or if it'll just be an "Oh, by the way" kind of drop during their press event, but it's going to happen.
Ideally, I'd love them to just show the PS3 tech demo they did, and then just flip the graphics up a notch to the PS4 version, but I don't know that we'll get more than a mention.
EDIT: Looks like that's been predicted a lot throughout this thread, so I'll be a bit more original and just say "Fuck it, Super Mario Bros. 4".