So, before we all overreact to this 'news' (too late), who's to say this is even a reliable source of information? Wasn't sourced all that convincingly so this could be just traffic fishing.
But look at things this way: if Sony has shipped as many Move controllers as they announced in a non-holiday release, is it conceivable that MS would ship out a smaller number of Kinect devices for a holiday release?
And, as I've mentioned in another thread (that of course was ignored), preorders do not represent shipments. Upon launch week, Halo Reach had just under 2 million preorders (allegedly), yet sold over 4 million during launch week. Were their shortages? No, which means they shipped even more. So don't put too much into preorder numbers being indicative of first week shipments OR sales.