There is a major difference between Wolrd IPv6 Day in 2011 and World IPv6 Launch Day in 2012 and that is that 2011 was a test day. The participants have enabled full IPv6 access to their main domains for 24 test hours in order to find out what the issues are. June 8 in 2011 was announced to not be a normal day in the Internet and users were made aware, that possbly some things would not work as usual. The goal of the day was to identify how big the issues are and what needed to be done in order to go real with IPv6 Internet. Many participants have not noticed any issues and have left IPv6 enabled after June 8 2011 (I bellieve this was true for approx. 60% of the participants).
So now, on June 6, 2012 (6.6.2012), on IPv6 World Launch Day the participants including Google, Facebook, Bing and many others (to be seen on www.worldipv6launch.com) turn on IPv6 forever, the website says “the Future is forever”.
So make sure you are part of it and enjoy!