D850 is such an overkill...
Sure new sensor tech and increased pixel count, but not everyone can afford that due to increased computer power needed...
Probably good for certain enterprises specialising in image restoration, archiving, archeological..........
IMHO 24MP should be the new standard for amateur models, 36MP for high-ama (semi-pro or pro backup body) etc.
D810 will be missed by many as it provides good and practical pixel count (and perhaps resolution, depending on lens use), compatibility with older workflow eg. with CF cards, pop-up flash for on-demand fill-ins (when without hotshoe-mounted flash)......
Press con on Monday... so what? Just brief reportage and hands-on, really nothing special