Nikon announced the D5 camera in January. The 'silly' video below from DigitalRev showing off the D5 is just a step above a commercial and shed little light on the performance of the new body.
You can read my post on the comparison between the Canon EOS-1D X Mark II vs Nikon D5 and see how the D5 'shoots at ISO 3280000'. I am expecting delivery of my Canon EOS-1D X Mark II in late April. Will be taking it on a few real world wildlife photo shoots around the globe and writing a comprehensive review soon. I have little doubt it will be a worthy successor to the venerable EOS-1D X camera.