And again.. Until we see these Head to Head, one can not really judge. Specs do not necessarily mean performance, otherwise everyone would be using Sigma 70-200s.
Both cameras seem to have their niches. Canon delivers it appears bigger pictures. faster burst, and likely better ISO.
AF looks to be a wait and see. Canon seems to be 61 versus 51, but we will have to see how the AF points work, especially if Nikon is did this as a last minute Rube Goldberg to make the spec, it may not function as well as people think.