Halcyon Habit from www.halcyonhabit.com sent me this interesting info: if you Google d700x site:www.nikonusa.com you will get two results (this search is looking for D700x keywords in all nikonusa.com pages):
This could mean that at some point of time Nikon USA had the following link online:
http://www.nikonusa.com/Find-Your-Nikon/Product/Digital-SLR/25442/D700X.html
Currently this URL points to the Nikon D3x product listing (because of the product #25442, the D700X.html portion of the URL is irrelevant) but Google cache did capture the full D700x URL:
If you search for D800 site:www.nikonusa.com you will get one result that currently links to a Nikon support page.
The part that is not clear is whether Google really cached this page/URL or just created this search result entry based on external links pointing to that D700x URL (for example the same D700x link was already discussed on Fred Miranda forum and maybe the Internet traffic to that URL from FM was enough for Google to create those entries). Unfortunately nobody knows for sure how Google search algorithm works and this D700x entry remains just another rumor.