Firstly, we have no PIs today in IPv6. If you're referring to pre-CIDR..I am behind on email due to flu but one thing I haven't figured out in this "GUPI" thread....what would be the difference to the PIs we have today? Aren't we trying to work around RIR policy with address architecture?
IPv4 prefixes, I think the difference is that people believe the scaling
issues with the DFZ will severely limit the ISP's ability to route
non-aggregatable IPv6 prefixes, however much money they are paid to do
so