OK kids, time to straighten out a few things.
I've never heard of a "D700m," just the plain D700, unless it's the name used in some markets.
This "D800" as proposed is a full frame sensor, not an APS-C. Also, ISO 6400 and above is VERY useful. There is no comparison between high ISO in a back illuminated CMOS sensor in a bridge camera and a full frame DSLR; at least for any photos you want to publish or sell to people.
I regularly shoot my D700 in nightclubs, caves, and local concerts, where flash is not allowed. I can go up to ISO 4000 before the dynamic range and colors start going south. One of the big selling points of the D3s is it can take clean photos at ISO 12,800 and even go up to 102,400 but the pictures are only marginal. And no, you don't need this for fireworks; those are really bright, you just need a steady mount and a 2-5 second exposure,
That said, I doubt this is real. Nikon normally releases first a flagship model, then a consumer one, a high speed sports one, and a large image size portrait/landscape one; but they haven't always been consistent Enhanced/improved models are followed by an "s" at the end of the model name.
The D3 was followed by the D3X, D3s, D700, and D300/D300s. There was no high speed model as there was probably no need since the D3 did well as it is, and the D700 was really what the D300 should have been.
The upcoming model should be the D4; the "D800" seems more like a "D700X" than something new. A lot of us have been hoping for a D3s sensor (which is different from the one in the D3) in a D700 body. This clearly isn't it, not does it make sense in Nikon's naming scheme and release pattern. Maybe it's all they can do after the earthquake and Thailand floods, but I doubt it.