Some In The Ubuntu Community Want To Fork, Maintain Unity 8
Marius Gripsgård who is known for his work on UBports, the community effort trying to port Ubuntu Touch to as many devices as possible, is determined to keep going and looking to maintain Unity 8. He wrote on Google+ yesterday, "I'm not giving up! I will do my best to keep Ubuntu touch and Unity8 standing on both it's legs! It will be hard. The Ubuntu touch wheel is still spinning, and it has enough momentum to spin until we start spinning it with hopefully with greater force. Expect some news and idea drafts from the Ubports team in the coming weeks."
Separately, there is now unity8.org as a fork of Ubuntu's Unity 8 code-base. "Following up with Mark Shuttleworth's announcement to abandon unity 8 development, we are planning to fork it and continue working with the project." The Unity8.org domain name is registered to a Ioannis Salatas, a name I wasn't able to find much about associated in the context of Ubuntu, but there is a John Salatas from the same address who has Linux development experience and has been involved with Linux development and is a former GSoC student.
On Reddit and elsewhere are others expressing interest as well in continuing Unity 8 development on their own.
I would argue one of their first goals should be to port it from Mir to Wayland (or X.Org) but it would be hard to see the community trying to mature and maintain Mir. At least with Wayland they still could pursue their mobile ambitions via libhybris and have more in common with Tizen and Sailfish. It's already challenging enough with a desktop fork, but for an obscure display server that has yet to see mainline support in Mesa, XMir isn't part of mainline xorg-server, etc, would be a huge maintenance burden plus having to maintain the Qt/SDL/GTK Mir back-ends and other unnecessary challenges when they could use the more mature Wayland.
It will be interesting to see what the community does with Unity 8 in the future.