I thought the Tyrell women stole this episode. The Grandma was hysterical, and she doesn't seem like someone to cross. But Margary in that last scene with Joffrey was just soooo smooth and manipulative. Best scene of the episode IMO. Love her! Her character on the show is way better than portrayed in the books.
Jaime was definitely weak and chained, but Brienne is also a bad-ass (remember she won a Melee against all of Renly's knights, including Loras Tyrell, to win a spot on Renly's kingsguard in the first place). Jaime at full strength and with no restraints would probably take her as he is one of the best, but in his current condition he had no shot.
Theon! All of these Theon scenes will be new for book readers. Should be good...but tough to watch!
I also liked the scene with Catelyn talking about Jon Snow as a baby and how she prayed for him to die, then prayed for him to live, then couldn't bring herself to follow through and love him. She never expressed a shred of remorse for her treatment of Jon Snow in the books which is one of the reasons I never liked her character much, so this was an interesting addition that makes her a little more sympathetic.