AFAIK you have to have native peering with them to be part of the pilot. At least, you did when we signed up. They may have relaxed that since.
According to a Google IPv6 talk I attended yesterday, they don't intend to relax that rule. Tunneling ipv6 connectivity over ipv4 is trash quality engineering and to be honest, its not a credible substitute for adequate ipv6 infrastructure.
<facetious> Tunneling ipv4 over mpls is trash quality engineering and it's not a credible substitute for adequate ipv4 infrastructure. </facetious>
Everything is a tunnel...
Indeed, but the differentiator here is that the transport for the tunnel in question also provides connectivity to the destination; i.e. - you can get to Google over IPv4. You do not (or, atleast I do not :)) have the option of connecting to Google "over" MPLS, Ethernet, etc. /TJ