As a 1080Ti owner I'm gonna take a solid pass on this gen. The only upgrade path that makes any sense here is a straight upgrade, i.e. GTX 1080 to RTX 2080 or GTX 1080Ti to RTX 2080Ti.
I ain't payin' north of one grand for a graphics card. Fuck that concept.
An upgrade from a GTX 1080Ti to a RTX 2080 makes no sense at all. You get the same performance, 3GB VRAM less and the only thing you gain, i.e. RT and DLSS, does not seem to be worth it yet.
It'll take quite a few more gigarays before that stuff really takes off. Besides, the gains in image quality are fairly minuscule and nothing you would really notice in the heat of the action anyway.
The BF V demo with the RT reflections was pretty impressive but it will be quite a while (RTX 4080 rather than 3080) before we will see playable fps at resolutions above 1080p.
So, gonna wait and see what nVidia will do on 7nm next year. Whatever it will be, I'm sure it'll be a much more worthwhile upgrade for GTX 10 owners. TSMC 7nm should give us a nice leap forward hopefully.