Jesus, talk about the emotional wringer. It always kills me when unemotional characters suddenly break down and can't stop themselves from feeling something intensely. This episode was like a veritable bonanza of that. Sherlock cried. One small tear, but it was definitely there.
I've seen plenty of speculation about exactly how he managed to survive his dive from the top of St. Barts, and I admit some of those theories are pretty compelling. But however he managed it aside, it was an absolutely brilliant scene. I don't think my jaw could have dropped any lower when, out of nowhere, Moriarty just shot himself. The man committed suicide just so he could 'win'. It gels in beautifully with the way this particular incarnation of Moriarty has been portrayed - not particularly greedy for money, luxury, or any of the other usual criminal mastermind trappings. This Moriarty just wants to be entertained, and he's so spectacularly fucked up in the head with the weight of his own intelligence and psychosis, that ruining other people's lives is the only way he can do it.
Sherlock saying goodbye to John was completely heartbreaking. Both Sherlock's inability to stop himself from letting his emotional control slip (again, he cried), and the way John just went completely to pieces after watching Sherlock 'die'. The daze he was in, completely unable to properly digest it. Brilliant acting all around.
Apart from that scene, I thought the idea of having Sherlock completely discredited and torn apart in the press was great. Anderson and Donovan really are characters you love to hate. The journalist (always and forever Jen from the IT Crowd to me, so I'm afraid I cannot remember her character's name for love nor money) was also enjoyably contemptible. And of course Molly, who was great. I love the evolution of her relationship with Sherlock, from silly, idealistic crush to being able to see the real him and all his myriad flaws, often more clearly than John because she has the advantage of distance.
I am of course simultaneously thrilled to discover that there will definitely be a third series, and horrified at the prospect of how far away it is.