The trivia items below may give away important plot points.
By the time this episode was shot the cast and crew knew that the show would be canceled. When Greg Edmonson wrote the music for the funeral scene at the end, he told Joss Whedon that he wasn't saying good bye to the character Tracey, he was saying good bye to the show.
Jonathan M. Woodward, who plays Tracey, has appeared in two other Joss Whedon series: as Holden in the "Buffy the Vampire Slayer" episode 'Conversations with Dead People,' and as Knox in the last two seasons of "Angel." Interstingly, all three characters appear friendly at the start but eventually turn out to be villains who are killed by the shows' heroes.