Christofer Hoff has proposed an interesting idea earlier today. He asked, "How many of the cloud providers (IaaS, PaaS) support IPv6 natively or support tunneling without breaking things like NAT and firewalls? As part of all this Infrastructure 2.0 chewy goodness, from a networking (and security) perspective, it's pretty important."
His post actual was a kind of epiphany which lead me to think that one of the great things about cloud computing is in its ability to virtualize everything. The cloud is a kind of "multiverse" where the rules of nature can continually be rewritten using quarantined virtual worlds within other virtual worlds (aka virtualization). The need for a traditional physical piece of hardware is no longer a requirement or necessary.
For example VLANs don't need to differentiate between IPv4 and IPv6; the deployment is just dual-stack, as Ethernet is without VLANs. So why not just use modern VLAN technology to "overlay" IPv6 links onto existing IPv4 links? This can be achieved without needing any changes to the IPv4 configuration and allows for seamless and secure cloud networking while also allowing for all the wonders that IPv6 brings. It's in a sense the best of both worlds, the old with the new.