News regarding Ubuntu 15.04 Vivid Vervet:

LibreOffice 4.4.3 has been addeed to the default repositories of Ubuntu 15.04 Vivid Vervet, so in order to get it on your Ubuntu 15.04 or derivative system, do:
$ sudo apt-get update
$ sudo apt-get install libreoffice
Ubuntu 15.10 Wily Werewolf news:
Ubuntu 15.10 Wily Werewolf is still based on Kernel 3.19, but the developers have announced that Kernel 4.0.x will be implemented by the end of next week, Kernel 4.1 RC being already implemented on the unstable branch of Ubuntu Wily.
Ubuntu Desktop Next, the desktop flavor of Ubuntu that uses Mir and Unity 8 as default, will be rebased on Ubuntu 15.10 Wily Werewolf and will receive UEFI support soon.
As a reminder, the first Alpha version of Ubuntu 15.10 Wily Werewolf will be released on the 25th of June and the second Alpha on the 30th of July.