Made the switch
My employer made the transition to IPv6 after a merger due to massive collisions in RFC 1918 address space. The only IPv4 addresses we have remaining are on the external side of our public facing load-balancers and a few firewalls we use for IPSec tunnels. All of our external DNS, mail, proxy, public VPN, and web servers are IPv6-only. We use a mix of IPv6, IPv4-to-6, and IPv6-to-4 virtual servers to make it all work. I wouldn't be surprised if we're still using address translation a decade from now, but I would be surprised if IPv4 traffic isn't the minority by then.
As for AWS now offering IPv6-only networks, I wonder if this will pave the way for them to start charging extra for public IPv4 addressing. Blocks of IPv4 addresses aren't cheap.