I've been using the D3x for some years now, and the 24 Mp size is quite enough in my viewpoint. Most prints, books, are just perfect (if the picture is good )! After years of film, I find that it surpasses it in cleanliness and sharpness. Already the D700's 12 Mp was almost perfect for most uses, the 24Mp add just some crispness. The question was about Mps, not the quality of the sensor in such things as low light capacity, color fidelity, levels of shades between black and white, etc. In all these, new sensor progress can be interesting (and necessary), and surely more important then expanding the Mp !