The update to glibc-2.12.2-1 increases the minimum required kernel version to 2.6.27. This kernel version was chosen as it is currently the oldest kernel with longterm support upstream. Users of the Arch "kernel26" and "kernel26-lts" packages are unaffected by this change.
Those wanting to continue the use of an older kernel version will be required to rebuild the glibc package with the appropriate adjustment made to the "--enable-kernel" configuration option.