Some pretty smart people have done quit a bit of work showing how good the D800 will be. Many people will not buy it for multiple reasons. IQ will be on the bottom of that list. It will probably have better DR at base ISO than any dslr.
I see your point. This is how I see it.
1. The theories expounded by Raw file analysts are not being disputed. We all know small pixels don't necessarily mean poor noise performance.
2. We've seen many cameras in the past which didn't perform the way theory would suggest. It's easy to find smaller sensors outperforming larger ones for noise. Look at the Nikon 1 vs M4/3 bodies. For an example of sensors in the same generation producing a noisier output when pixel counts are increased look at the Nex 5N and 7.
3. Nikon's last generation of cameras used the same sensor in two bodies differentiated by price. Canon did the same thing. This time round they've diverged and both companies are limiting the pixel count in their flagship bodies. Two sensors cost more to develop than one so margins are down on both bodies. They have a reason for doing this and in Canon's case it's clear they would have done anything necessary to compete with Nikon on low-light performance.
4. Nikon could have used any sensor they are capable of developing in any body they sell. Speed is a factor of the shutter engineering and processing speed not the pixel count. Canon have shown that a slower processor can simply be doubled, or tripled, to meet speed requirements when pixel counts rise. Nikon could produce a high-res, fast body if they choose to. It would almost certainly be cheaper to use two signal processing chips per body than to develop and fabricate a new sensor. Saying pixel counts are forced down to keep speed up doesn't make sense.
The point isn't that more pixels are bad. They're not. It's that Nikon and Canon are behaving exactly the same way and making the same decisions about how to produce their best cameras.
Both the 1D X and the D4 are being sold on the basis of their excellent noise handling. There has to be a clear advantage to justify the expense of creating two sets of internals, when both companies previously used one. Both sought the best low-light images and the result was Nikon pushed pixels up conservatively and Canon pushed them down.
If either company could bring high MP and great low-light performance to the table now they would. The theory doesn't matter in light of the fact of their actions.
We won't know exactly how the bodies perform until real tests on finished bodies are done. Until then the argument seems to be between people who trust in the theory and people who trust in the companies expertise.
I am trusting in both. I think the arguments are valid but for reasons I don't know, in 2012 both companies see a noise benefit to lowering the pixel count.
If it's not the case, and the real world performance is almost identical, for the first time in history both manufactures will have made the same huge mistake in the same generation. People will abandon the flagship bodies and we'll never see a low pixel count on a professional body again.
I think that's unlikely. I could be wrong.
