A couple things I took away from this episode:
1) The North plotline is back on track. Bran and co will continue on and like Steppricon said, Jon gets to return triumphantly, giving him more cause to be named LC. Issuses I have with this plotline are, based on the timeline I don't think we'll see Mance attack the Wall this season and Stannis come North (especially since he is apparently in Braavos next episode). I'm guessing the climax of Jon's season will be Ygritte and Tormund's attack on the Wall. I also feel a bit sad for Ygritte's (lack of) plot in this season. We've only seen her very briefly since Jon's "betrayal" and the next time we see her is probably when she's killed. As for Bran, I guess the detour to Craster's was a way of giving that story a bit of substance before the Cave and, to me, definitely means no Coldhands.
2) Dany's plotline is pretty frustrating, as it was in the books for me. She has her army and her fleet, I feel the only reason she isn't going to Westeros right now is because George doesn't want her there until the fina showdown. Jorah even brings up that Westeros has never been more ripe for the taking. A boy King, the ruling family's army has been devastated by war, and a bunch of people who think that their King is a bastard and would likely join a true cause. I've always assumed Dany will abandon Meereen at some point...I don't know how she can undo thousands of years of culture in a few months, especially after she leaves.
3) The Lannister mines being dry is indeed a huge plot point. The crown owes both the Lannisters and the Iron Bank millions but since the Lannisters basicallly are the crown, I guess that debt gets forgiven because Tywin can't pay himself back. The Lannisters clearly need the Tyrells for their money but I wonder if the Tyrells figure this out and ally with the Iron Bank/Stannis as well.
4) Cersei's acceptance of Margaery seems to be a huge departure from the books. I think she was being sincere in this scene. She's already told Margaery to never touch her or call her sister again, so why play nice again? The only reason for this that I can think of is maybe Cersei thinks that once Margaery and Tommen renew the Lannister-Tyrell alliance she can weasel her way out of marrying Loras? I don't think this wedding will actually take place so unless Loras meets a bad end soon, I think this may be their angle.
5) Good set-ups with Lysa being a crazy bitch, renewing the disconnect between Arya and the Hound who were becoming a bit too chummy, the brief mention of the Sand Snakes.
6) Pod and Brienne were funny together. I think this duo might turn into another fan-favourite. Interesting to note that they are making for the Wall. I wonder if they make it there and what the consequences would be...
7) Is this the only episode with no Tyrion?? A dark day indeed.