Is Agent Coulson Really Not Dead?

Collider has the following from Clark Gregg about it:

I’ve been so happy and living this geek fantasy as they kept adding Agent Coulson to everything including The Avengers and then gave him this magnificent, almost Shakespearean death scene, and I found out on that day how much I loved this guy and had come to identify with him partly because of the way fans responded to him, and also because he had such a great niche in those movies. He got to be funny, he got to be, in this case, heroic. And then I got to say good-bye to him, and it was a very emotional day. And yet I feel what Joss did with that was a fantastic conclusion of the character. And even though my friends at Marvel said, “You know, we spent a lot of time talking about how Coulson lives, and we know that there’s a movement out there, and there are t-shirts and people paint on bridges ‘Coulson Lives’, we’re going to bring you back”, and it’s one of the many things people tell you that never ever happens. And then I get this call from Joss saying, “Well…there’s a script. And here’s what we’re thinking, and it’s after The Avengers, and here’s the concept.” By the time Joss finished telling me, I was in.

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After people see the show, they’ll have some clue as to why I’m still there, still breathing. But I don’t think they’ll know everything…