The next Ubuntu version is expected to be released in few days (the 17-10). This version will be the first to come back to gnome. It will mainly lean on wayland, even if x11 will remain, at leat for a while. Wayland, seem to be the future. What about Pantheon? Is there a group working on this? What is the next version of Ubuntu that will be taken to release the next version of Elementary?
As said over there at Google Plus, there are some blockers to rely mainly on Wayland, like "no support of Struts for Wingpanel, need to create an alternative to libbamf for Plank". libbamf uses X, there is no Wayland alternative. I fear there will be no full support for Wayland in Juno, but there is a BountySource.