Included in this new release are major driver updates to the PowerVR graphics and Wi-Fi firmware, along with changes to the NAND memory driver which will improve overall system speed and stability. The Linux kernel and several drivers are installed as Debian packages for easier future upgrades.
Further improvements include adapting to the monitor resolution at boot, a DRM-based PowerVR SGX driver that enables applications to use the X window manager, increases in Ethernet download speeds (from 30 Mbps to 70 Mbps), and some file-system optimisations to speed up boot time.
Details of the software release are available in a blog post at Imagination, here;
In the same post, Imagination's Alexandru Voica lists a number of updates to Android 4.4 for the same board; and promises an imminent Android 5.0 release.