We estimate that .05% of systems may fail to fall back to IPv4, so some people may find Google, Facebook, Yahoo, Bing and other participating websites slow or unresponsive on World IPv6 Day.Google has a tool posted at <a href="http://ipv6test.google.com/">http://ipv6test.google.com/</a> that you can use to test your own connection.'Ready for prime time': Planning for World IPv6 Day began las