1. How would you determine impressive turns?
2. You couldn't replay it even if you wanted to without A. Maintaing a video of the last turn played, and saving it if it was the highest so far, highly ineffiecient. B. Replaying the game until you got to that turn, putting unnecessary strain on the usere's computer, after a substatial delay.
3. Where would it go?

I'm pretty sure I read somewhere that the current engine can't do replays, so this would never happen, nevertheless, it would still be cool.

Also, your name sounds familiar...

Like if someone racked up 85 points or more in a turn for the computer to temporarily save that turn until the end of the round. If its not possible then it's not possible and I'm sure everyone will still live. But it would be a cool asset I guess just hypothetically

This has come up several times in the past.

Doing that would require snapshotting the entire engine state at that point in time, then playing forward from it again.
It isn't impossible, just very complicated, easy to cause unexpected consequences (w/ networking, scripts etc), and thus, unlikely to happen.

A simpler version where a small capture of part of what's currently visible on the screen was done could be implemented more easily, but still has questions of performance - besides the fact you'd have to force the camera to what you're wanting to capture.

A far simpler one where the game goes into "slow mo" if the game judges it to be cool would be easier to do, but hard to judge the appropriate circumstances.