Surprisingly Nikon will introduce another camera in their "crowded" FF line between D610 and D810...
http://nikonrumors.com/2014/08/11/the-upcoming-nikon-full-frame-dslr-camera-will-be-marketed-as-an-action-camera.aspx/#more-78882It is supposed to be an "action" camera which will supplement D4S, much like D700 did with D3/D3S.... Given that the new body is expected to be "faster" than D610, with 51AF system and "sensible" size files, I wonder what the name may be and what sensor will be used into it...
My first guess for naming would be D620 based on the following scenario: Nikon's naming policy for the last 5 years is four digit/odd starting number for APS-C (DX) bodies and 3 digits/even starting number for FF (FX) bodies... Thus, one might have expected an FF D400 in the line, but this would suggest a lower price model than D610, so it can't be... Alternatively, what may be smart, is that Nikon may introduce this as a part of the D6xx series, let D610 price fell further down and then replace D610 with a "new" D4xx line....
My guess for sensor would be for the 16mp one that they already use in D4S and DF... The guess is based on the following: 1. It will provide a sensible "upgrade" link to D700 owners, 2. It is "their own" exclusive sensor & 3. It is a great performance sensor...
Anyway, whatever the name or the resolution might be, there seems that they have realised the marketing mistake they did by
not providing a real replacement of the D700 when D800 was first introduced... They disappointed most of their FF marketing base at those days (with the completely different D800) and they where penalised (marketing wise) for that...
It is a widely spread (and discussed) subject that D800/E introduction should have been a D800S(16mp)/D800E(36mp) combination in the first place, given that they had both sensors available at those days.