Addison remarks to Derek that Meredith is "young". In real life, Kate Walsh was born in 1967 and Ellen Pompeo in 1969, an age difference of only two years (and Patrick Dempsey was born in 1966).
First time Cristina tells Meredith "You're my person".
First appearance of Joe's bar.
Sarah Utterback (Olivia) is now billed as a guest star after being previously credited as a co-star.
Every episode of the show is named after a famous song. "Raindrops Keep Fallin' On My Head" is a song by B.J. Thomas.