Nikon is done with the new products announcements for 2011. Something really big is coming in January 2012 - Nikon has bought space for a LOT of ads in big photography magazines for January 2012. I know they use to advertise a lot, but in this case, the extremely high amount of ads next month is a sign that they plan to reveal something big. Since we are talking about professional photography magazines, I can only think of the D800 and maybe even the D4 and not a consumer level camera. On the lenses front, we are still waiting for a new 18-300mm DX lens and a new AF-S 85mm f/1.8 lens. The Coolpix line will also be upgraded, probably in February, with a replacement for the Nikon Coolpix P300 that will have a new 24-100mm f/1.8-2.6 equivalent lens.
Today the French website shots.fr published an article called "Des annonces produits Nikon début janvier 2012. Et une dispo en février" which translates to something like "Nikon product announcement at the begining of January, 2012". The post is now removed, but you can still see it when you Google it (unfortunately Google did not cache it):
Announcement at the beginning of January makes sense because the PMA show will take place on January 10-13, 2012 in Las Vegas and Nikon can get a lot of publicity for their new products.