Here's what we know though:
T2 is going down.
The Shrek closer sounds imminent.
I've been told Fear Factor isn't coming back after HHN and that it's just "quietly going away."
FFurious is still a 2019 opening.
IF KidZone goes down too, it would be a DHS-level decrease in available attractions for the Studios. More importantly, we would be looking at FOUR new construction projects (with Dragons' replacement) PLUS a new land in whatever replaces KidZone just in the parks. Looking at it that way (and adding the hotels), it's entirely possible Comcast or Universal drew a line on the budget for their existing parks. If that's the case, a Shrek, T2, FFurious and Potter add-ons may be "cheaper." Because they'd still be budgeting the 4th Gate.
If Park4 features Nintendo, Kung Fu Panda/Berk (Dreamworks), and the Monsters, they could have a smash hit.