Obviously the name of this episode refers to Jon Snow peacing out at Castle Black, but lets talk for a minute about some foreshadowing that may be happening...
Ned Stark's Valerian Steel sword was melted by Tyrion Lannister and turned into two swords after he lost his head. If what I am remembering and reading is correct one of them is now Jamie Lannister's and the other is Bryanne of Tarthe's. Bryanne's is called Oathkeeper. Not sure what this has to do with the price of beans, but Sansa is on her way to Castle Black with Bryanne (and Oathkeeper) where Jon Snow just left (Oathbreaker- is he really an Oath-breaker though since he technically served until he died?). Also, did anyone notice he left the cloak with his appointed new leader but definitely dipped off with the sword.
Also this week was the return of Rickon Stark. Several fan theories here. We see the head of Shaggydog but was it really him? The Lord Umber was fiercely loyal to the Starks so it doesn't make sense that he is betraying them now. Also he would pledge allegiance to Ramsey Bolton (silent cheering). This could be a trick to over-through the Bolton's.
Finally, did anyone catch the foreshadowing that Arya threw out. She definitely said that The Hound was alive when she left him and that she no longer wanted him dead. Could this be setting up an attack on The Mountain and House Lannister???