So I'd say now Canon is on the wrong track in terms of image quality. 1D3: 10MP APS-H = 17MP FF. So it has slight advantage over 1Ds3/5D2 in terms of high-ISO performance because of its lower pixel density. Unless 1Ds3/5D2 are using the different (newer generation) sensor technology from 1D3, which from what I have heard is not the case. 1D4: 16MP APS-H = 27MP FF. So if 1Ds4 is over 30MP, it will be the same game as 1D3 over 1Ds3/5D2. You just cannot beat physics, period