CR has no control of DPR reviews, so we don't know the answer. However, the question has been asked many times on DPR, and the answer is always the same. They conduct testing after they get a camera to test, and spend a lot of time carefully testing it. It takes a very skilled person to conduct the test, and since they received the D800 first, it was done first. The 5D MK III will probably be ready in 2-3 weels or less, based on past timing.
CR does not yet have a dedicated professional camera tester / reviewer, and you may not see a review right away. They are changing the forum software to vbulletin, and that is a really big job to switch and to import all the posts to new software. The final result will be more and better features, but it might be a bit of a learning curve at first. I've played with the beta version a bit, it works well for a first rough cut, but there are issues with importing posts with images. There are only a couple of long time members able to try it at this point, so don't ask, I can't link anyone.