An exact shipment figure from Microsoft would help put all this to rest. 66 million vs something like 66.8 million makes a somewhat significant difference, but I think even a flat 66 million would put them at a higher shipment figure for the calendar year?
In the grand scheme of things, shipped eventually equals sold anyway, barring total failures like E.T. and the Virtual Boy.
The shipped vs sold disparity only really tells us about each company's short-term momentum, but that's pretty obvious to everyone at this point, and it can be determined well enough with VGChartz's figures.