About the Tesseract, he reveals this.
"Yes. It is [an Infinity Gem]. I don't know when we'll actually divulge that necessarily, but it's the space stone."
What about the Aether?
When asked if this trend would flow through Guardians of the Galaxy, or if it would continue all the way through Phase Three, Kevin Feige reveals both...
"Well the answer to the first question is both. It is both. And then, you know? Who knows? If they allow us to keep making movies, it will go a little bit further."
He also briefly commented on the return of Hawkeye, who seems to be getting the short end of the stick in terms of Marvel movies.
"He definitely plays a very large part in The Avengers: Age of Ultron. So that'll be the next place to further evolve the Hawkeye character."
Lastly, if you've already seen Thor: The Dark World, you know that it ends on a sort-of cliffhanger, just like any good latest issue of a comic book should do. Kevin Feige explains what happens next.
"I think there's always room to touch on it in other stories, but I think we wouldn't get the full evolution of where that story's progressing until another standalone Thor film."