Recently new DLC called The War Machine has been announced. Now you can see all of the additions in action:
 

The content of the first DLC pack called The Resistance was revealed! It contains:
 
3 multiplayer maps
 
Anthropoid â€“ Prague, Czechoslovakia
Occupation (remake of the map Resistance in MW3) â€“ Paris, France
Valkyrie â€“ Masurian Woods, East Prussia
 
New War Mode mission – Operation Intercept  
Takes place in France where you have to secure Resistance fighters transported by train
 
New Nazi Zombies mission – The Darkest Shore  
Takes place on an island north of Germany
 
 
The Resistance DLC comes out on January 30th, first on PS4.
 
Information was taken from official Activision's blog: https://community.activision.com/t5/Call-of-Duty/Revealing-the-First-Call-of-Duty-WWII-DLC-Pack-The-Resistance/ba-p/10558846