CNET has put up a piece on John Boyega about Star Wars, The Force Awakens, and Finn which is really cool:
What he will say about the movie is that Finn is on a journey, much like the origin stories of gods and superheroes from other mythologies. “All the characters we love — Batman, Spider-Man — never ever start off as those guys,” Boyega says in his rich British accent.
More on Finn:
I think Finn is a very interesting character. Finn is going to represent that classic “Star Wars” story and that classic “Star Wars” narrative. We have all these new characters coming in, but Finn is going to be one of the characters that carries on the narrative that we all know from the original.
So, for me, it felt like it’s necessary for my guy to be introduced — and introduced with a bang — because his story is not as straightforward.
Everybody’s asking about the mystery of who Finn is. He’s a mysterious guy so far, and no one has any clue what’s going on with him.
I suggest heading over and reading the full piece.