D800 - two card set-up for Eye-Fi
When I cycle thru my photos, I notice the CF in the lower left portion of the screen information. when i get to the last photo, then the next photo will be on the SD card. It will switch back and forth at the end of each batch of photos. I believe that even with NEF, you only are seeing the jpg portion of it. If you want to check for focus, zoom in on it.
I am very, very easily amused.