Glad the show is back, as I'm a Moffat fan. But the episode is a B or B-. As others have pointed out, it's a lot of smoke and mirrors, a great big plot revealed non-linearly, which is fun, but at the cost of …. something. Heart, perhaps. A lot of new info, but at times it felt draggy. And a few too many handwaves.…

I suspect there are too many episodes
One of the reasons I felt CoE bordered on great (and would have made it, if it stuck the landing) is that it was a story in 5 episodes. It was tight. I think it could have been shrank by 1-2 episodes (most of Ep 2 was run around and wait), but it moved well.

Well, I certainly thought I was wrong. I'd be fine with being wrong. But to me Matt Smith's "But we kissed!?!" and the fact that something was written on his crib that clued him off seemed to be pointing that way. (Presumably only his parents wrote on his crib).

Wait, River is the Doctor's Mom?
I thought I was imagining this as a reading, but it seems to me that it's still possible. Is that the consensus of how things worked out? (Matt Smith's reaction "But we kissed!" and gong ugh! seemed clear enough). If it's true, it's certainly an unexpected reversal.

I thought of the Jekyll reference as well. And just because the script was written by Neil doesn't mean that Moffat may not have tweaked it. Or perhaps Neil just liked that line from Jekyll and put it in as a subtle homage or inside joke.