Seems to me that they've basically just made mirrorless versions of the D850 and D750. For a company like Nikon, I'm glad they seem to have got the majority of things right on the first go but I agree the single slot thing is very strange. Probably wouldn't affect me too greatly as I'm not really doing any paid work these days but I can understand how it would be a deal breaker, especially for people who shoot high volume critical stuff. I'm also a bit disappointed they don't seem to have managed eye detection as this is probably my biggest 'woah' thing from the Sonys and would make portraiture a lot easier. I'm still very keen to see what comes of the Z mount. I'm hoping the dimensions of it will allow some super wide lenses with smaller footprints (i.e. a 14/15mm that I can use my 100mm filters on). Don't really care too much about the super wide aperture stuff like the Noct other than the 'oh that's pretty cool' factor. Happy enough with my D810 for now. If it came to be that I needed a backup body, I might consider one of these but will probably just buy the 2nd or 3rd iteration once my D810 gets really long in the tooth.