With the head of the Luminous engine joining the development team as part of the restructuring a year ago, and in the light of Versus FFXIII using a modified Crystal/Luminous engine. I am willing to bet that some, if not all of the Luminous engine will be the base for the new FFXIV. Whether or not they support DX11 is another question, since they still want to keep PS3/PC parity etc etc.