Susan Arendt said:
This not only creates a completely new dynamic for the show (which is good, because it was getting a wee bit stale), but also setting up the unfortunate "Doctor who?" line at the end of the episode. Yeah, it echoes the end of The Wedding of River Song (2011) in which "Doctor who?" is revealed as "The first question. The question that must never be answered. The question that" the Doctor has been running from his entire life ... but it's dumb. Yeah, it's a play on the show's title, har, har. It was stupid last season and it's stupid now. I hope they drop that particular shtick soon.
Firstly, while it got milked a bit at the end of the episode, the idea of a series based around the idea of "Doctor Who?" has a lot of promise. Since Moff took over one of the underlying currents of the show has been what is The Doctor really like if you strip away the rose-tinted glasses the people of Earth have for him because he likes us. So far we've had:
The Pandorica Opens said:
A Goblin, a Trickster, a Warrior. A nameless terrible thing soaked in the blood of a billion galaxeys. The most feared being in all the cosmos. Nothing could stop it, or hold it, or reason with it. One day it would just drop out of the sky and tare down your world.
A Good Man Goes To War said:
A man who can turn around an army at the very mention of his name. Doctor. The word for healer, wise man throughout the universe. We get that word from you, but if you carry on the way you are, what could that word come to mean? To the people of the Gamma Forests the word Doctor means Mighty Warrior.
The God Complex said:
An ancient creature drenched in the blood of the innocent. Drifting in space through an endless shifting maze. To such a creature, death would be a gift.
In this episode we find out the Doctor doesn't keep his name among the Daleks, but instead is known as "The Predator". I wouldn't be surprised if this is the running theme throughout this series, meeting different species who all have their own name for him either from previous meetings or legend. I would also dovetail nicely into a multi-doctor episode for the 50th anniversary as a case of "We've shown you how other species see the Doctor, now how does he see himself?"
On other areas of the episode, I didn't see the twist coming, but thats due to me never looking particularly hard because in my opinion that just spoils all the fun. I'd be surprised if Oswin and the new companion arn't related in some way. This is partly due to the fact all the fans and press who saw screeners were asked to not mention who was playing Oswin until after it had aired as they wanted to keep it a secret, and partly due to Moffett being someone who plans ahead to a surprising degree.