You don't necessarily need individual VMs to be IPv6 addressable to do this. That is, since our global load balancer already supports IPv6 termination, your app's API or website or whatever will be served as IPv6.

Take a look at our announcement from last week for more info: https://cloudplatform.googleblog.com/2017/09/announcing-ipv6...

Disclosure: I work on Google Cloud (so I indirectly benefit from you using our services)