Don't know? Maybe it would never be done. Maybe some of the devs would leave v2 and go for the v3 fork? As you said, it isn't a small project so how many devs can they lose to a v3 fork and still maintain v2?
I just think these are all important questions that should be considered.
Can someone simply look at any changes the v2 code implements and use that as *inspiration* to implement those changes in v3? Of course, not direct copying since that brings up other issues.
I am mostly just messing around. I wish the HURD would pick up some steam and a hell of a lot of features or maybe solaris?????