There're tons of guesses and ideas about the plot of Doctor Who and how it will develop in the second part of season 6. I especially like The Incomparable Podcast and their theories. Since I finally got my girlfriend to watch DW I'm going through it again myself and there're facts I've missed or forgotten.

There's a woman produced in 04x06 - The Doctor's Daughter who is something between Doctor's daughter / clone / duplicate with realigned genes. She's way to militant for Doctor's taste but gradually bond between them grows stronger and in the end she saves him by jumping in front of the gun of the crazy-green-brain-guy. After Doctor leaves and she's being prepared for her funeral she regenerates - same body but effectively comes back to life - and gets to space ship to have some timey-wimey adventures.

Now, I know it's not Moffat's episode and it's a long stretch and doesn't make any sense at all, but she was the only female we'd seen regenerate prior to the girl in the season six pilot. Some family reunion would be nice to make things fun.

Second, more relevant fact comes from 05x02 - The Beast Below when Amy tries to prevent Doctor from discovering that the whole space ship / UK is powered by giant space-whale creature. When he finds out he's pretty cross with Amy and says: "You took it upon yourself to save me from that. That was wrong. You don't ever decide, what I need to know."

And Amy did it again with his death, but she told him eventually (thinking he was the flesh-Doctor). There haven't been much time since then to elaborate on that because of all the melting flesh-people and defeating armies, but I'm pretty interested, if it'll play out somehow in September.