Here's why I think there won't be a Nikon D400 yet in August

[Stany Buyle]

While there is a rather big possibility that D4 and D700 successor will have different sensors for different purposes and aiming a different public, there is a realistic chance they will be released together within a couple of weeks.
For the above statement I partly rely on Bryan Peterson's prediction, more than on any other prediction(http://www.fotografie.fr/fotoforum/viewtopic.php?f=18&t=1210), and insinuations of a friend of mine who works in this industry.

I think Nikon wants to attract D300 users to FX format first, while big lenses is big money...
And last but not least and TMHO, the announced or rumoured 24Mp DX Sony sensor wasn't available early enough to announce a Nikon body with that sensor this August. The March 11th catastrophy delayed many things in Japan... According to that same friend, a D700 successor release was technically about ready before March 11th.

A D400 will for sure come, but probably later.

Just my thoughts...

[James]

Nice reasoning Stany,

I think that they must feel that they are losing ground in the DX market though. I had a play with the D7000 last weekend and as much as I liked it overall I felt that the AF was not as flexible as on the D700/D300 cameras. (I imagine that it was as fast but I couldn't see how to change modes as quickly and how to have flexible af point control - my D700 i snormally in 9 or 21 point and I choose where it starts).

So the D400 should be the perfect good light sports/wildlife camera if the ISO performance and IQ is on a similar level to the D7000.

But that doesn't change what they CAN do if they've had fabrication or supply issues. I would guess that if they are using the same sensor as Sony and Sony really intend to be one of the top 2 camera companies then Nikon will only get sensors after Sony.