Here are a couple of things I liked:
1)Benedict realizing that he keeps flipping/twirling props in 2x01, and finally saying "I've got to stop doing that."
2)Benedict cringing over his violin playing and how he got the bowing wrong (This makes me automatically forgive him for getting the bowing wrong.)
3)Sue Vertue saying that the Sherlock+Mycroft scene in the hospital makes them more human, while simultaneously either Moffat or Gatiss says that the scene is about how they're both freaks.
4)Russel Tovey spending all of the 2x02 commentary asking everyone questions - seriously, the boy should have been a journalist. He asks about every bit of the process and is genuinely interested...and he's got a great laugh. I may have developed a little crush on him, just for being so adorably inquisitive.
5)Hounds was originally scripted with some scenes in a different order - which is why the joke with Sherlock's collar is backwards. His muttering "It's cold" was originally supposed to come AFTER John calls him out on flipping up his collar in order to look cool. Apparently Moffat and Vertue had a huge fight over the re-editing for this (and most likely other reasons too.)
In other news, when the DVDs do come out for region 1, I was thinking of doing proper rewatch posts (S1 and S2) for Sherlock...like I do for Supernaural. Would anyone be interested in that or would I just be talking to myself?