The Zones of the Broken Isles

The Broken Isles will be our new continent - an area somewhere near the Maelstrom that was the old capital of the Night Elf civilization before the Sundering. The area is described as a graveyard of the civilization, and presumably we'll see a lot of indications that most of it fell into the sea.

The continent will be made up of six zones, though as of yet we don't know exactly how the levels will be arranged. Our first stop will be the Broken Shore, which is home to the Tomb of Sargeras - the point through which the Legion is pouring out of the Nether. I'd assume that the Broken Shore will work somewhat like Tanaan - we'll start off there, but then come back perhaps for the final raid.

Stormheim is the home of a group of Vrykul who sailed south, and seems to be where the portals to their good and bad afterlives are (both of which are dungeons.) These Vrykul I believe have an evil God-King who has cast his lot with the Burning Legion. And if I recall correctly (unless it's elsewhere) this is where two Titan Watchers have been battling against each other for thousands of years.

Highmountain is home to another Tauren variant and some kind of creature called I believe a drogbar, which seems like it could be related to the Trolls. This was what Neltharion called home before he got corrupted into Deathwing, so I wouldn't be surprised if we find some Old God stuff here (jeez, as if the Legion weren't enough!)

Val'sharah is where Malfurion learned to be a Druid, and it's also where the Satyr loyal to Xavius have been trying to use a corrupted World Tree to spread the Emerald Nightmare.

Azsuna, I believe, has some Titan ruins, and we'll be racing against Queen Azshara to get one of the Pillars of Creation here. I don't know if Azshara will be truly one of the expansion's major villains, or if she'll survive this fight and live on to have an expansion of her own.

Suramar is the old Night Elf capital, and it is inhabited by the Nightborne Elves - a group of Elves who have flourished by going even crazier with magic than the High Elves, and are now loyal to the Burning Legion.

We know that there will also be some areas in older continents like Class Order Halls, though they haven't revealed exactly where all of those are. At least one - the Warlock one - will be outside of Azeroth.