Olympus Japan announced that it will start shipping the E-M1II on December 22. It’s not clear from the text if that is valid for Japan only. So far US stores still mark December 12 as the official shipping date (see Amazon US).
Olympus E-M1II preorders:
In USA at BHphoto, Amazon, GetOlympus and Adorama.
In Europe at ParkCameras. WexUK. Digitech.ch.