You wanna cool the CPU, not the chipset. Chipset should be fine.
There doesn't seem to be any confirmation it fits but I believe AM4 should have the same space as AM3+
I'd wait and see
Its been confirmed, the mounting pattern is different (But the ASUS Crosshair VI Hero offers AM3 and AM4 mounting patterns). All the water cooler makers have been offering free AM4 upgrade kits though, but its best to contact them to confirm its available.
I'd just get with a customer support tech for them. I ordered a Corsair H60 cooler for my new Ryzen build and gave them a call. Luckily it'll fit as it doesn't bolt on. It uses the clips that the AM3+ boards had. In short take 5 mins and call them if nothing else you can at least get the adaptors shipped out and on the way to if they're needed.