Dev notes on WoD:
Pre-Expansion Patch
The patch with the events leading up to Warlords of Draenor will be released close to the expansion release date.
We have met Garrosh's friend with interesting ideas about how to use time on the Timeless Isle. We will hear a little bit more about this friend in the pre-expansion patch.
The vision with Anduin and Garrosh is a hint, but we will see more of the story in the pre-expansion patch.
Story
Khadgar from Outland will accompany us in the expansion, as well as coming to warn us that something is going on with the Dark Portal.
The Warlords of Draenor starting experience will send you through the Dark Portal to try and shut it down from the inside. It is roughly an hour's worth of content where you are trying to stop the Iron Horde.
It is possible that the Alliance and Horde will work together against the Iron Horde at some point in the expansion.
The Isle of Thunder style solo scenarios might be used for a few of the major points during the questing experience.
The Blood Elf Paladins have an interesting history with the Naaru, so they will show up again in Warlords of Draenor.
The Dark Iron Dwarves will go through the Dark Portal and be a part of the Warlords of Draenor story as well.
Garrosh gets things set in motion, but then things are out of his control. We will see him for a while and then find out what happens to him.
Misc
Players will likely work together with their guild to cover all of the different specializations for Garrisons.
Lorewalker Cho doesn't really fit this expansion, so it isn't likely we will see much of him.
Dave Kosak used to be the Lead Quest Designer, and is now Lead Narrative designer. The job was so big that it was split into Lead Narrative Designer and Lead Quest Designer.