Ice is "Track Changes" in JavaScript
nytimes.github.com
nytimes.github.com
That would be anwesome feature. Then you've literally created a peer review system. Well at least the basic building blocks.
I for one would find this very useful.
We wanted the focus for ice to be on change tracking only so we intentionally left out track changes presentation/interaction details. I think there is a lot of potential for good UI/UX tools to be built for the track changes that ice produces and I would love to feature them in the project wiki.