If you wanted a far out in left field, seat of your pants guess, I'd say that it's a semi-soft sure thing that if you look at the performance of the GTX 960 on the Devil may cry 4, you'll probably come fairly close to what the 1060 will probably do on the latest version.
Realizing that the 1060 is going to perform about one tier better than the 960, but that the demands of the game are going to see an increase (usually) over the previous version, you end up with about the same performance if you're looking at similar resolutions and settings. So games get harder, but you get a bigger card, and everything breaks even.
Obviously, the second biggest factor is going to be what CPU the card is paired with and then what resolution you're playing at, so there are simply too many variables to make any sort of educated guess you'd be willing to stand behind, but at least that might get you in the ballpark anyhow.