IPv6 uptake (was: The Reg does 240/4)

Several people in NANOG have opined that there are a number of mail servers on the Internet operating with IPv6 addresses. OK. I have a mail server, which has been on the Internet for decades. On IPv4. For the last four years, every attempt to get a PTR record in ip6.arpa from my ISP has been rejected, usually with a nasty dismissive. Today, I'm trying again to get that all-important PTR record. If I'm successful, then I expect to have my mail server fully up and running in the IPv6 space within 72 hours, or when the DNS changes propagate, whichever is longer.