***If you haven't seen the Southern Raiders, then leave now. Spoilers ahead.***
If you have then you'll notice Katara forgives Zuko and hugs him. (Awww, sweet)
And Aang, in the Ember Island Players Trailer, Told Katara, "I thought we were supposed to be together." In which she replies, "Not now", or "this isn't the right time."(Sorry, couldn't remember what she said exactly.)
Anyways, perhaps she said that because she has emotions for Zuko now. I don't know.
And in the Ember Island Players Preview at Comic Con, Aang attempts to take a seat next to Katara, in which Zuko takes instead.(Hmmm, looks like Zutara to me. Maybe.)
I use to not be a fan of Zutara, but now that I think about it. It could be interesting to see.