[Aang is a bit taken aback by this. Something definitely isn't right. And he has Sokka's words about different times fresh in his mind. He doesn't want to accept what is actually the truth right away, but he is considering the possibility that he's talking to the Katara of the past.]

That'd be great, Katara. I can't wait. I'm... there's a bunch of buildings nearby and I think I see fountain over there.