This is a BIG feature in Apple’s Final Cut Pro roadmap.
What is means is that a number of Editors or collaborators can work on a project at the same time, either over a network or via the cloud.
Apple has received a Granted Patent relating to a system for collaborative media editing in a networked environment. Specifically the patent primarily relates to Final Cut Pro and collaborative editing in real-time.
The Patent for Final Cut Pro relates to collaboration on media production. In one example, one or more media projects are produced through the collaborative efforts of at least one originator (or “the originator”) and one or more collaborators.
There is a detailed discussion of the Patent and implications at Patiently Apple