+1
see also:
http://forum.mikrotik.com/t/ipv6-and-nat-how-i-changed-my-mind/100481/1
http://forum.mikrotik.com/t/nat64-and-dns64/38531/1
http://forum.mikrotik.com/t/features-request-nat64-dns64/85661/1
Internet-Uplinks going IPv6 only. Small IoT devices stick to IPv4.