Fedora 11, codenamed Leonidas, was released on June 9, 2009.
Some of the features in Fedora 11 are:
ext4 as the default file system
experimental BTRFS activated by IcantbelieveitsnotBTR at bootup
Faster Bootup aimed at 20 seconds.
GCC 4.4
KDE 4.2.2
Gnome 2.26.1...