From the announcement:
The weekend is here so I’ll keep this one quick and easy. We have a new faction our for Grimdark Future with the Mercenaries. There are guns for hire that can be added to any faction, and include units for the Human Inquisition and Elven Jesters.
On the Age of Fantasy side we don’t have a new faction per-se, but instead a modification of an existing faction with new units. The Forces of Havoc have been re-named to be the Havoc Warriors, and there is a new book where you can find rules for Havoc Warrior Disciples. These include all sorts of cool new units such as the furious Gore Reavers, savage Birdmen, pestilent Plague Kings and crazed Lust Warriors.