I hadn't been bowled over by Matt Smith's performance prior to this episode, but I thought he was excellent here in an episode where the focus was on him.
I loved the use of Elizabeth's note left in his briefcase. The first time Philip reads the note, I believe he sees it annoyingly as a warning, a guideline she's setting for his behavior, "Don't forget you have a family." Then, after the interview with the journalist where she opens old wounds of the broken family of his youth and the ensuing homesickness it awakens, he looks at the note differently. "Don't forget you have a family;" a place where you are loved, missed and where you belong. Nicely done, show.