I was pointed to this report from OfCom, the UK communications regulator, through this commentary.
The report is dated 2012 and has some interesting statistics comparing the deployment of IPv6 in various countries.
I found the following quote (emphasis mine) from the report interesting as I read through.
The report finds that by any measure, the UK lags behind its peers in IPv6 deployment. Whether in comparison with; economies of a similar size, G20 and EU member states, or with Asian economies, the UK is behind in IPv6 adoption. IPv4 address exhaustion and a failure to transition to IPv6 has a significant impact on innovation as it is the essential building block for any technology that connects to the Internet. Failure to keep up with competitor economies will have an impact on the UK’s consumer access to broadband, on eGovernment, […]
The report includes a brief discussion of the IPv4 exhaustion & transfer market, IPv6 deployment experiences, and deployment costs.