A while back it was decided to create a separate Ubuntu 14.10 Utopic Unicorn ISO running Unity8 on Mir, including the new core apps:

"The goal is to ramp up the quality of the unity8 desktop, without destabilizing our current environmenent. For that we are going to keep an unity7 image and add a new one for unity8 on the desktop, that new iso should become the default one by 16.04".

The new testing "flavor" is called Ubuntu Desktop Next and a daily ISO is available for download starting today. However, the ISO is still work in progress and for now, it still includes Xorg (needed for the current LightDM greeter and Ubiquity) and also, the list of packages that will be included on the ISO is marked as work in progress, so the default package selection should change.

Building an unity8 desktop image According to the blueprint , there are still quite a few items on the todo list, including:

make unity8-greeter usable on Desktop;

set up testing for the new image;

look at feature gaps in the greeter and things we need to implement

get the installer working at least in only-ubiquity (installer only) mode, installing from the live session is a wishlist item for this cycle;

look at pre-installing click packages on the ISO.

more information about tne new Ubuntu Desktop Next ISO, check out today's Unity8 Desktop Preview Image Forabout tne new Ubuntu Desktop Next ISO, check out today's Unity8 Desktop Preview Image UDS session

Download the new Ubuntu Desktop Next 14.10 (Utopic Unicorn) Daily Build*





(the username is "ubuntu-desktop-next" - without the quotes - , and the password is blank which means you must simply hit the enter key)

* In my test, the current daily ISO didn't work properly and the Unity8 session failed to start (and I've tried it in VMware Player - which is supposed to support Mir -, and booting off an USB stick) but maybe it was something related to my system, I'm not sure. However, given that the not only Ubuntu 14.10 Utopic Unicorn but this ISO too are in early development stages, that's to be expected. Hopefully the ISO will work soon - I'll retest and let you know when it works.