My view is that the Zeiss glass was clearly superior 5 years ago, but with recent releases such as the 105mm f1.4, 70-200 f2.8 E FL, 19mm T/S, 24mm f1.8, 28mm f1.4,... Nikon has caught up in technical qualities and is now overall ahead in terms of look.
I have only kept my Otus 55mm f1.4 and have sold my other Otus in favor of the Nikon equivalent. The Otus 28mm and 85mm were still a tiny bit better but the lack of AF, less rugged build, higher weight and bulk were far from compensating the slight advantage in image quality.
Cheers,
Bernard