1) I was ready to murder-death-kill-destroy everyone at BBC if Jenny had been killed off for real.
2) Holy shit, seeing Strax suddenly going full Sontaran against Vastra was scary! I'd been so used to the awesome bumblingness of Strax that seeing him go bad because The Doctor never changed him was a scary, unexpected surprise. Seeing him get in a bar fight in Glasgow, though, was fucking awesome.
3) Loved all the cameo bits with the various Doctors of the past.
4) I get the feeling that's the last time we see River Song. A fitting ending, especially with "Goodbye, sweetie." I'm assuming from now on that The Doctor's name is actually Sweetie.
5) John Hurt?!!?
The going theory on Hurt right now is that he was a regeneration of the Doctor between 8 and 9. In other words, he was The Doctor involved in the entire Time War. That would make sense within the hints we were given about him. However, if this is true, then the other theory is that this makes Hurt The Doctor #9, Eccelston #10, Tennant #11, and Smith #12. I really hope they don't go and re-number the previous Doctors. Not only because it's how fans have discussed their favourite Doctors (outside of the actor's actual name), but Smith's run on the show especially has had all sorts of fun little jabs at him being #11, like the soccer jersey.
Of course, that brings up the OTHER theory about Hurt... They're going to call him The Valeyard, an old Doctor villain from times past, and was apparently a future regeneration; his thirteenth - and last - regeneration, in fact. this is all theories right now, but that'd be pretty awesome. Some more on The Valeyard here:
http://tardis.wikia.com/wiki/The_Valeyard