I need to watch it again. Total headfuck of an episode, which can't be bad really.
I am both very pleased with and quite cross at the special. The end where Watson shoves Moriarty off the waterfall and then Sherlock does a slow motion swan dive kind of thing into it felt very Doctor Who.
I loved the Victorian part and I was thrilled when I realized it had come back to modern times Sherlock, but then as it went on I got less thrilled. I was delighted to see Moriarty back, less so when it became patently obvious it was a dreamlike Moriarty.
In terms of plot it comes down to little more than Sherlock leaving the plane. It was explained that Sherlock was attempting to work out how Moriarty faked his death (and it was confirmed that no body was found) with the body-switch scenario, etc, yet he decides at the end that Moriarty is actually dead after all, so nothing much was gained.
If Moriarty is dead, as they keep stressing, then Moffat and Gatiss need to make their peace with it and stop writing mind palace scenes and flashbacks for him. He's been featured in three episodes out of four since his death...