Speaking of which, the BIG REVEAL.
I've seen some discussion that the reveal is less powerful because fandom guessed it, which makes for interesting observation about the effect of fandom on a serialized piece of fiction, one in which we have time for mass speculation. It wasn't so much that fandom guessed it as much as it was in our list of possibilities, and got more and more probable with each new episode this season, which started narrowing things down. River Song's around a lot! And Amy's pregnant-not-pregnant! And there's a little girl! Who's in a spacesuit! That was put there by enemy aliens! Who may have shot the Doctor! Hang on, isn't River in prison for having killed a man? And her timeline's all wonky to ours? And Amy just had a baby girl! So if River had turned out to be something completely unrelated to this storyline, would it have been more or less satisfying? I can't blame Moffat for properly laying down his material so that everything fits. I do think that the swift among us might have seen "Melody Pond" at the very start of this episode and got their confirmation as early as that moment (I am not among the swift, I admit), or put together that River couldn't be there because she had to avoid time paradoxing herself (I'm not that swift either, that just came to me while typing). But those are intraepisode anvils. Which I still didn't see until the time came to see them.
From the first appearance of River we've had speculation on who she is. If she'd turned out to be the Doctor's mother or Romana or Leela or any of the other speculations, would we say that we had guessed it? I suspect we would have, the same way that (Harry Potter semi-spoiler) "Snape was in love with a particular character" was on our list of possibilities even though we had nothing to confirm it until we were told it, and it felt less powerful as a result. We like it when even the hivemind of fandom can't go where the authors are going, don't we, but we don't want things to come at us from so far out of left field that we call it a cheat. Kuroshitsuji II episode 8 is my go-to example of "We've laid the groundwork with this character but haven't given you enough to guess; now here's almost everything in one episode, prepare to gasp" in serialized fiction. I think, with River Song's Big Reveal, I am too pleased that this was no cheat to be disappointed that the answer actually was in the list of guesses. I look how far back the groundwork has been laid and am too impressed to be disappointed.
Other small notes:
-CHAMPION LA LECHE LEAGUE MACHO LACTATING SONTARAN. To the end of my days I will cherish that. It's like the joke about how if men had periods they'd brag about how heavy their flow was.
-Also to be cherished to the end of days: "Whyever do you put up with me?" *thirty-foot lizard tongue sleepy-stinger dart* *shared naughty look* MOFFAT DIDN'T HAVE TO GIVE US THAT NAUGHTY LOOK. HE COULD HAVE PRETENDED THE SEQUENCE OF SPOKEN LINE AND TONGUE HAD NOTHING TO DO WITH EACH OTHER. BUT HE GAVE US THAT LOOK OMIGOD.
-I do want to see the moment when Lorna the soldier meets the Doctor when she's a child. I suspect we'll be given it by season's end.
And so it shouldn't be lost in all this: did anyone else fall out of their chair laughing at the sheer balls of the next episode title? I really can't emphasize SHEER BALLS enough. I mean, you couldn't name a South Park episode that and not call it sheer balls.