David Burnett started his career in photography using Nikon cameras, before selling all of his gear for Canon. Now 40 years later he is dumping Canon for Sony. It sounds like the Sony a9 was a major influence on his decision to dump Canon and even he thinks that he will have plenty of extra frames to choose from with the irresponsibly fast Sony a9. David also sounds very impressed by the Sony a7RIII and mentions that he will be shooting at the 2018 Olympics in Korea with his new cameras.
It is interesting how many professional photographers have done videos about going mirrorless in recent months. It almost seems as if Canon and Nikon might have missed the boat entirely on the move to mirrorless because there are a few mature mirrorless options available today and it took time for them to get that way. I don’t think that Canon and Nikon can release professional mirrorless cameras an get it right immediately to catch up with the competition, so the makeup of the camera market might be changing quite a bit in 2018.