From Wed 06 June 2012, Google, Facebook, Yahoo, Akamai and many others will provide their websites over IPv6 as well as IPv4.  A number of network operators and router manufacturers are also participating.  Network operators (including campus networks) can participate by committing to connect 1% of their users over IPv6 - details can be found at www.worldipv6launch.org

For those who have not enabled IPv6, let us repeat our advice for IPv6 Launch Day 2011, about problems that can ensue for IPv4-only networks,

The two main causes of the problem are:

• incorrectly configured devices on an IPv4 only network, or
• an incorrectly configured IPv6 network

In the case of a misconfigured machine, the test must be run on the user's machine, and the incorrect configuration reversed. It should not be necessary to disable IPv6, as it is likely that there is an incorrectly configured tunnel set up on the machine.

In the case of a misconfigured IPv6 network, the problem is solved by restoring full IPv6 access.
We in the HEAnet NOC did not receive any reports of problems as a result of IPv6 launch day last year. However, your support staff may still wish to add these checks to their troubleshooting steps.
If we can help in any way, please contact us: noc@heanet.ie