I shoot a D200. I bought a D800E which had the focus problem and returned it rather than fight the, in my opinion, ridiculous repair procedure offered by Nikon. I also want a D400 if and when it is offered (assuming that it the build quality, etc. is comparable to the D200/D300 cameras). However, since we don't know if Nikon is going to produce the D400, it seems that shooting a D800 in DX mode should be a reasonable substitute for the D400. If my math is correct the D800 in DX mode would produce about 15 megapixels, which is a little more than the D300s. I am patiently waiting for the focus problem to become a matter of history (some say that we are now there) and do plan to buy a D800E anyway. So maybe I don't really need the D400 (unless, if produced, it offers more fps, important for sports, or other features that are significantly better than the D800 in DX mode).
What are your thoughts on this? I sometimes shoot action (American Indian dancers) in low light, so I need all the reach I can get, hence the need for DX mode.