What he doesn't mention is that Nikon does not have a 135mm f/2, or a 100-400mm lens that are in the same ballpark as the Canon lenses. For landscape with the D800 and the 14-24mmG, a landscape shooter will be very happy. However, my D800 was very noisy as ISO got up to 1600, but it took NR very well. However, a low light shooter might not be very happy with it.
Looking at the manual for the new 600 EX RT, the wide angle adaptor now pushes the range to 14mm at the wide end. It's another indicator that reinforces my assumption that a Canon 14-24mm lens is in developement. But I get the feeling that Canon are taking their time with their lenses and want to get things right and not rush to market a half baked product. In the mean time....there's the new Sigma 12-24II, which looks pretty amazing and is a lot wider than the Nikkor. The Current TS-E 17mm is pretty amazing optically and with a bit of shift, it can equal around 12.5mm...although it's a bit of a faf.
On the Nikon front, the lack of a Nikon equivalent 100-400L may seem an issue...but Sigma make a very good 80-400 OS which is pretty close to the Canon in IQ and performance.
I'm waiting for a 100-400IIL to arrive too....sure it's going to be at least another year before we see anything on the shelves, but if it's in the same league as the 70-200mm 2.8 L IS II, then it will be worth the wait.
The recent 70-300L has had it's critics, but the one I tried a few months ago was stunning in every area. It's build was fantastic, it's AF was very very good and it's IQ was top tier. It's expensive but worth everry penny IMHO.