For all of its advantages, the 1D X is a replacement for the 1D IV and not the 1Ds MkIII, which is why the "flagship" question keeps being asked and why the "high megapixel 1D-series" rumours keep doing the rounds. If you are a 1Ds MkIII owner, then you probably value image quality at low ISOs and build quality. The 1D X is not an advance over the 1Ds MkIII in this respect, so their money either stays in their wallets or gets spent on non-Canon equipment. For this reason, I expect that a new "flagship" high resolution 1D-series camera will come along as soon as Canon has the sensor ready, to compliment the "flagship" action camera (i.e. the 1D X).