Eleven barely registered Amy and Rory's agreement in the weirdness of him calling them mum and dad. Having let go of Rory, he was now busy staring at River. A Pond? But that's not... he wasn't... he couldn't be... He was...

"Um... River. I don't think. I'm just the Doctor. I don't even have a last name. Could you imagine me swooping around the universe saving the day as 'Doctor Pond'? 'Don't worry! Doctor Pond will save us!' That sounds more like a country doctor making house calls than a Time Lord."