There's just TOO MANY THEORIES! I have enjoyed this series very much, but in a sort of 'argh my brain hurts from all the meta' way. I can't *wait* for the finale, because then not only will we know all the answers, but I will be able to go back and rewatch all the eps with all the puzzle pieces in place, and it will hopefully be a much more relaxing experience!

My vote is going to a combination - I think she's a Dawn Summers-eque creation of Gallifrey. She IS a 'normal girl' but she has been created as a normal girl for a purpose - I think that purpose has something to do with Gallifrey, and that she will 'activate' or realise it herself through some Tardis-related, Bad Wolf type shenanigans.