I actually liked how they handled the fall, because while they didn't tell us how he survived, they introduced enough elements that you can put together a plausible theory. I don't need to have it spoon fed to me, I just need to know it was possible, and some of the elements they came up with (such as the girl's reaction to Sherlock meaning that there must have been a Sherlock doppelganger out there) were quite clever.
The first episode had some good comedy, got things back on track, introduced Mary and had a cool short little mystery to whet the audience's appetite for the season. The second episode was probably the most fun from the show's run so far. I liked the emotional touches at the wedding, I liked the ridiculousness of the bachelor party and the mystery of the Mayfly man slowly being weaved into the wedding was nicely written.
And the final episode was amazing. It was going to be hard to top Moriarty as villain, and lets be honest, he probably didn't. But it was still a great performance from a truly despicable character. The drama with Mary was really interesting and really well acted by both her actress and Martin Freeman.
And motherfucking Moriarty!! I don't know if he's alive, if he set something in motion before he died, or if Sherlock just created that video to get himself off the hook, but I'm just excited by it either way. Moriarty on this show has been the most inspired portrayal of an iconic character since Heath Ledger's Joker, and anything that might keep that guy in future episodes sounds great to me.