I don't know Danuser mixed up all these weird ways of talking about the "In Balance" universe. In the Campaign he started talking about the good ol "Song of Creation" which is very much inspired by Tolkien and how Discord struck the Song and brought it out of harmony.
But, then here he's talking about the Pattern.
The Pattern in this would theoretically be Equilibrium of the Cosmic Forces. The Universe in which our player characters exist is in changed itself from the common conflict of Light versus Void as told in the Chronicles to one that was quickly dominated by Death and we became Guardians of the Pattern once we defeated Zovaal as no one is grabbing Azeroth for themselves anytime soon. Of course, they could throw this out with Azeroth waking up and it having a different meaning or a completely different meaning entirely from even that (hard to tell without Cinematic). But it is not a good title to have based on the whole hint hint nudge nudge of how bad the Universe is from Zovaal and Sylvanas.
We just reverted it back to the state of which it is supposed to be which is Reality being fought over by Light and Void forces. (At least according to The Pantheon of Order)