However, if you can make a compelling reason why we should prioritise it (other than 'I like tinkering with stuff') I'm very open to hearing it.
Both Microsoft (Win 7+) and Apple (OS X 10.10+ and iOS 8.4+) mainstream IPv6 over IPv4
In fact, in the very latest Apple versions due next month - OS X 10.11 and iOS 9, Apple are specifically delaying usage of IPv4 A records and waiting for IPv6 AAAA records before using IPv4. (Refer: https://www.ietf.org/mail-archive/web/v6ops/current/msg22455.html) Most network engineers agree that latency and throughput is better on IPv6, against direct IPv4 and CG-NAT.
Lack of support for IPv6 at the ISP level will mean users are getting a reduced experience and response times, not only from better latency and throughput but also because their Apple devices are delaying and waiting/trying IPv6 first.
I expect Windows will also very shortly follow the same principle in the next WIn7 and Win8 SP's.