I'm very relieved Jon Snow got through that alive and well. Now that his mission is more or less complete, though, the whole event rings a bit of a strange note. A successful operation, but with what consequence? What did we learn, exactly? What significant development, character or otherwise, happened? I cheered when Locke died, but for something with so much build up, his failure came rather suddenly. Maybe you're simply supposed to take pleasure in the fact that, yes, House Stark is still capable of fighting back, as well as the whole "justice is done" thing. Something about how it all came together weirdly lacked emotional resonance, though, at least on my end. I'm guessing the operation's success will have more consequence down the road.
On the other hand, the non-fighting parts of this episode were mostly great. Particularly the revelation about Littlefinger's involvement with Jon Arryn's death. That seriously came completely out of nowhere. Lysa went from off-balance but somewhat sympathetic to just simply off-balance this episode.