At the virtual Ubuntu Developer Summit this week, one of the interesting sessions was about how session inits from Upstart could be migrated to systemd. The topics discussed were, "a) How the current Session Init architecture could be made to work should PID 1 be systemd rather than Upstart. b) Whether systemd provides some sort of compatible framework. c) Whether the current architecture should be switched to a systemd equivalent (if available)."
Talked about during the session were how systemd runs on Android's kernel, systemd and Upstart user sessions can be present on the system in parallel and switched at run-time, and any thoughts about using KDBUS is being deferred until it's production ready.
Those interested in the systemd migration talk for Ubuntu Linux can find all of the session notes via this page while the session video is embedded below.
More interesting for end-users will be Mark Shuttleworth's comments about systemd that occurred during his vUDS keynote. After saying Mir will be the default by Ubuntu 16.04 LTS, he said the same about systemd. In regards to systemd, Shuttleworth thinks there will be "a preview for people to use pretty soon." He then said systemd will become the default somewhere along the road to Ubuntu 16.04 LTS in being careful not to break users running Ubuntu Linux.