While Buffy, Spike and Faith are fighting in the graveyard, Faith asks "May I?', before taking a stake from Buffy, a nod to the first time Buffy and Faith met in the season three's Faith, Hope & Trick (1998), when Faith asks the same thing before taking Buffy's stake to dust the vampire she is fighting.
Faith's line, where she offers a theory why the blind Bringers are so good in battle, was cut: They say your other senses get better. Maybe all blind people are smokin' in a knife fight... Not saying it's likely.
Dawn and Faith recognize each other, despite never having met before. This is further demonstration of the spell that the monks cast in Season 5 to make everyone in Buffy's life believe that Dawn had always been Buffy's sister.
Faith mentions to Willow that someone tried to kill her while she was in prison, as shown in the episode of Angel titled Salvage (2003).
Caleb's line to Xander that he "sees everything" references Xander's conversation with Dawn in Potential (2003), in which Xander said "I see more than anybody realizes because nobody's watching me."