Doctor - "Two points in space and time that should never have touched"
In "Flesh and Stone", the Doctor realizes the crack in time is the same as the crack on Amy's wall. At the end of the episode, he realizes it's her - Amy.
Doctor - "It's you! It's all about you! Everything. It's about you!
Doctor - "Amy Pond... Mad, impossible Amy Pond. I don't know why, I have no idea, but quite possibly the single most important thing in the history of the universe is that I get you sorted out right now!
What I want to know is what are the "two points in space and time", and what have they got to do with Amy?