Here is new info about the conference.
Tetsuya Nomura Details Fabula Press Conference (andriasang.com, 12.21.2010)
Video footage will be the main focus of the January event, said Nomura. He contrasted this to last week's Jump Festa event, where demos were the main focus.
Asked what games to expect at the event, Nomura said, "In addition to the Fabula Nova Crystallis related titles, there will be Kingdom Hearts Birth by Sleep Final Mix, Kingdom Hearts 3D and Dissidia Duodicim Final Fantasy."
So I now believe we will get KH3D footage or a trailer.