A first review
Martin Bailey, a Tokyo based photographer has posted a pretty extensive review of the Canon EOS-1D X. You can read or listen to his podcast as he talks about his initial impressions of Canon’s new flagship.
From the review
OK, so these are the main points that I’ve come across so far. I can live with the resolution for the frame-rate and high ISO performance trade-off . I was expecting a larger leap forward in the AI Servo tracking performance, but I’m very happy with the accuracy of the AI Servo focusing when it locks on. For my cormorant tests I was working in very high contrast conditions, and with flowing water in the background, which has always been very tricky. Considering this, it performed OK, though I had hoped for a little more.