That the Nikon D3 has been introduced with a full frame sensor (approximately equal to 35mm) to compete with Canon’s EOS 5D. Both cameras will crop images from their 12 megapixels to about 5 megapixels if used with digital rather than full format lenses.
This isn’t a fault, as they were never made to use DX (digital) format lenses.
Anyone buying an EOS 5D or a Nikon D3 will know full well that they need to use full format lenses (those designed in the first instance for 35mm film cameras). That’s the idea of making a full format digital camera; pointless if you use digital lenses on it.
Nikon say:
“The D3 delivers full resolution 12.1 megapixel images at up to nine frames per second when used with conventional AF-NIKKOR lenses. When used with DX NIKKOR lenses, the D3 automatically switches to the DX-format mode that uses a cropped portion of the sensor to generate 5.1 megapixel resolution images. While in this mode, the D3 automatically masks the portion of the viewfinder that will not be photographed.”
Whoever is slagging off the D3 for doing what it's supposed to do must work for a rival company