The DC animated universe had shared continuity back in the 1990s when the "Batman," "Superman," "Batman Beyond" and "Justice League" animated series were on the air.
For much of the past decade though, Warner Brothers abandoned that idea. Instead they've released standalone direct-to-video movies based on DC Entertainment comic books from "Batman: The Dark Knight Returns" to "Superman: Doomsday".
With this month's "Justice League: War" though, that changes back to shared continuity again. Producer James Tucker says: "This will definitely be the first salvo in doing new films that are in continuity with each other. Our next movie is going to be 'Son of Batman,' and that Batman will be the same Batman that you see in 'Justice League: War'. Basically, we'll have two concurrent series of Justice League movies and Batman movies, and they'll be in continuity with each other. So it's kind of world-building."
The plan is for two home releases each year based in a shared continuity universe, with an additional stand-alone, continuity-free DC animated project every year. This year that standalone will be an animated film based on the successful "Batman: Arkham" video games.
Source: Heat Vision