I think, before they move to systemd, Canonical will try to polish unity for their next LTS. Not to mention the fact that they have to eventually move Unity (which still uses version 2) to GTK3 (not sure if they already announced this yet). Imagine having to update Unity to GTK3, while keeping it neat, and developing new or reintegrating old features and moving from upstart to systemd al in the space of one year (12.04 is the next LTS, right?). That might not be much for companies like Google or IBM or maybe even the likes of Apple but the size of Canonical made even developing the current version of Unity somewhat daunting.
At least this is my opinion. Maybe someone has better insight. Would you have Canonical be all over the place for the next 12 months?