Yesterday Nikon formally announced the much-rumored D3X. The D3X is basically just a D3 with more megapixels. Or is it? The D3X has 24.5 megapixels while the D3 has 12.3. However, the D3X frame rate is 5 FPS while the D3 is 10 FPS. Apparently, doubling the megapixels halves the frame rate. Why? It appears...