One more Age?

In the Dev Diaries that just dropped Matt Owens writes:

One More Age. By providing interesting new unlocks at the end of a game, we're hoping players not only feel better rewarded for the effort of closing things out – but also have a compelling reasoning to explore and experiment with exciting new options.

Is this the "4th Age" we've been talking about or "just" different game modes that yiu can start playing after victory has been achieved (by yourself or another civ)? What does it mean with respect to expecting an Information or Future age in a DLC?

I'm so excited but I don't know what to make of it. What do you all think about it?