Nikon Rumors got their hands on a new patent that Nikon has put in for what seems to be an interchangeable sensor camera. From the looks of it, the camera also looks a bit like a DSLR of some sort with a traditional mirror and pentaprism. To change the sensor, the user will have literally just snap the back downwards and change out a unit of some sort.
Sound familiar to you? This is how medium format backs work. In the film days, various backs had various films. In the digital days, there are just backs with LCD screens and all. If Nikon is trying to change up the way they do things with giving users digital backs instead of full cameras, it will be an interesting approach.