Knoppix 7.4 was released yesterday with an updated package set and shipping with the LXDE, GNOME 3.13, and KDE 4.13.3 desktops while the lightweight LXDE desktop is the default. Knoppix 7.4 is powered by the Linux 3.15 kernel and already has in its package set the X.Org Server 1.16.0 release.
While upstream Debian is still working towards systemd support, Knoppix is proactively working in that direction and with the 7.4 release there is partial integration with systemd while using a workaround to use its quicker, script-based Knoppix system start with sysVinit. Knoppix 7.4 also pulls in the new version of the Compiz 0.9.11.1 window manager. Knoppix also has finally picked up experimental support for UEFI booting after installation on a USB flash disk.
More details on the Knoppix 7.4 release can be found via Knopper.net.