World of Warcraft has had largely the same World PVP system since it launched way back in 2004: you pick a PVP or PVE server in the beginning, and that determines if players can freely attack you or vice versa. The server division was a hard one; the only way to change from a PVE to PVP server is to start a new character on a different server, or transfer your characters. This ends up with situations where players who dislike world PVP end up on PVP servers because that's where their friends are, or PVP-centric players are trapped on PVE servers.
During today's "World of Warcraft: What's Next" panel at Blizzcon 2017, game director Ion Hazzikostas said this is finally changing. Server divisions are going away completely and world PVP will be a per player toggle. Want to just quest? Turn your world PVP toggle off. Want that real-world Horde vs. Alliance experience? Turn it on. It's your choice.
Hazzikostas says there will be additional bonuses to balance out the inefficiency of having your world PVP toggle on. They don't know what those bonuses are yet, but they want to make it worthwhile to join into world PVP with others.
This is frankly a huge change that World of Warcraft has needed for some time. I hate world PVP, but my primary server is a PVP one, because that's where my friends were. Now, I no longer have to live with that restriction.
The beta for World of Warcraft: Battle for Azeroth is coming soon, but the expansion itself does not have a release date.