It means that the series never died (which a lot of people assumed). The team that makes the game are still "active" in developing games meaning that they could work on a game now if they want or started already. This of course is up to them.
Though for your answer. There -could- be a DOA6 for early news, but honestly it's up to them. It just means that the series itself isn't dormant or like expired IP because they are still interested (from the looks of it) in fighting games.
Just like with every other vague announcement, it doesn't mean anything... Its just KT's way of Poking you, letting you know that: "Hey, We still exist."