Amazon sent out an email to everyone who has a Nikon D800/E pre-order with an estimated arrival dates of January 2013. This is obviously an error in their system, probably caused by the large number of pre-orders in a short period of time. I expect the Nikon D800 to start shipping in the second half of March and the D800E in the first half of April 2012.
Update: B&H lists the D800 shipment date as March 22nd, 2012:
This is the full email sent from Amazon:
We now have delivery date(s) for the order you placed on February 06, 2012 (Order# ***):
"Nikon D800 36.3 MP CMOS FX-Format Digital SLR Camera (Body Only)"
Estimated arrival date: January 04, 2013 - January 08, 2013
We hope to see you again soon!
Customer Service Department