I liked Amy's "never could resist a keep out sign" and that she could pick locks. Also tied in nicely to having to have proof it was a spaceship, as per the opening sequence. And the Doctor's state of denial about getting involved was amusing, and clearly he never believed it either - nice that that tied into the ending, too. I liked his line about "I'm going to stay out of trouble! ... Badly." too :) It seemed packed full of references to other things, too - Star Wars most notably, but also Pratchet and I've seen pointed out since that the get up Liz 10 was wearing was reminiscent of Phantom of the Opera although my first thought was about V for Vendetta for mask-wearing people. And the premise as a whole made me think of "The Ones Who Walk Away from Omelas" which is an Ursula Le Guin short story that I'm not entirely sure if I've read or not, but I've definitely read about it a lot, it's one of the classics, really.
Liked that the Doctor didn't save the day as well - as I saw someone suggest somewhere else online the arrogance of the end of the 10th Doctor's life is being somewhat dented. We also had "last of my kind" explanations, with less angst and trauma (as you'd expect being on his third life since then, gotta be getting more perspective on it). Of course Amy's way of saving the day was very impetuous - she thought she'd figured it out and then just did it (after a token attempt to attract the Doctor's attention). Which is, of course, the girl who can't resist a keep out sign, and the girl who runs off with the madman in his box the day before her wedding, too ;) The wedding seems to be something she has been having doubts about anyway - did she just get engaged coz she'd been abandoned (she thought) by the Doctor again so might as well get on with "what's supposed to happen" in her life?
And Daleks next week! Interesting to make the set up not part of the trailer, but actually part of this episode. The trailer raised more questions, but J's unspoiled by the trailer so I shan't say any more :)