Yes, yes, Johnlock, I know! But here's the place to discuss Johnlock in TSOT without "polluting" all the other topics with our fantasies 
Well, to be honest, I hadn't expected so much Johnlock feels in an episode focusing on John and Mary's wedding.
I won't discuss all the obvious things (but feel free to do so, hehe!
) such as Sherlock's speech wich almost sounds like an open love letter to John, or that epic, overwhelming hug which almost had me in tears.
To me, it almost feels like Sherlock is the one getting married to John, or even to John AND Mary as he has accepted her (and says at the end that he'll always be there for the two of them, well, three of them actually!). As a matter of fact, when the photographer says "just the bride and groom please", he doesn't even realise he shouldn't be on the photograph.
The things he says to John in his speech, "I'll never let you down", that actually sounds like the promises you make to your other half on your wedding's day. He could as well have said "I will love you and protect you until death do us apart", awww
At the end he says "My last vow", it's an allusion to next episode, of course, but it reminds me again of wedding vows.
All that thing with that client when they're drunk (just after they played "Who am I?". Oh, by the way, John grabbing his knee...
"I don't mind". Well, I certainly didn't mind either
). I can't help but think it was a kind of double meaning. I mean, she's there, saying things like:
* "we seemed to automatically connect" : isn't what happened for them in ASIP??
They decided to share a flat while the day they met! Remember Mycroft "Hm and since yesterday you've moved in with him and now you're solving crimes together. Are we to expect a happy announcement by the end of the week?" hehe
* "such interesting conversation, it was lovely" : John even smiles and glances at Sherlock at that point
* "I wish things had gone further": there, Sherlock suddenly takes off the arm which he had placed on the back of the sofa, just behind John's shoulder as if he was thinking just the same after that night of complicity --and years of friendship-- they've just shared, as if it had come to his mind, and that he was suddenly realising it was no good as John was about to get married, and so he shifts away from him
* "I don't know, this is special": that's exactly what their relationship is! Whatever we see in it, love or very strong friendship, it IS special.
Then I don't know but what did you think of that girl (the bridesmaid) telling him "I wish you weren't... whatever is you are" and that he replies "I know". I know I'm seeing this with my Johnlock glasses so I'm probably reading far too much into this, but actually, I don't see what she was implying. She barely knows him. I feel like she's in love with him but thinking "shit, he's in love with John, it's obvious, so he doesn't swing my way". Yeah, well...
And finally, that sad look on his face just after he's made that deduction about Mary's pregnancy like he's feeling that John is slipping between his fingers, going further and further away from him. He tells Mary and John to dance (while he LOVES dancing but has no one to dance with as even the bridesmaid is having fun with another guy). And then he realises everyone is moving on with their life except him and he he is lonely in a crowded place... awwww 
So what are your Johnlock thoughts after this episode???