With the release of Fedora 8 on the immediate horizon, Bill Nottingham of the Fedora Project announced the End of Life date for Fedora Core 6 as Friday, December 7, 2007.
As a reminder, the Fedora Project supports a release for a full month following the second successive release. So, because Fedora 8 is set to be released on November 8, Fedora Core 6 will no longer receive official updates after another month. Confused? You can find more information regarding the Fedora life cycle on the Fedora Project Wiki.
At one time, the Fedora Legacy Project provided updates for older versions of Fedora Core. Unfortunately, that project has been shutdown and will not take on Fedora Core 6.