I liked this one. I thought it held together really well, thematically, and it really brought the entire character of Ben Linus out front and center. He used to be a man of such mysteries, but now his motivations, his weaknesses, his good sides and bad, they're all brought out in the clear. His doppelganger's lecture in the beginning--about Napoleon getting to keep his title of Emperor, but it meaning nothing as he was exiled to an island for the rest of his life and stripped of any real power--informed Island Ben's decision later on to reject the Man in Black's offer of protecting the Island once everyone else had left. There were lots of cool little moments like that, actually.
We also had some little things confirmed to us:
--There are only six candidates left.
--Frank didn't pilot Oceanic 815 because he overslept.
--You can't commit suicide if the Island chooses you...but someone else can kill you. That answers a pretty big one about Michael. He couldn't kill himself because he was a candidate, but the Man in Black, as Christian, finally got him killed through the loophole of Keamy's bomb.