Nikon has filed United States Application US20110194020 today. It appears to be for a digital camera, and a continuation of a previous patent (12068231) filed on February 4, 2008.

Nikon Announced the D3 and D300 on August 23, 2007.

Nikon Announced the D700 on July 1, 2008.

Here is the new patent application filed today:

Nikon Patent Application August 11, 2011 (US20110194020A1) PDF (437 KB)

(Note: The diagram is a generic one used in several previous patent applications.)

Could this be the D4 or D800?