The musical score from the pilot episode is used throughout this episode.
When Ryan tells Taylor he just wants to be friends, she answers "Ryan Atwood, mon ami, sounds terrif". She said the same thing in The Summer Bummer, when Ryan suggested they be friends.
The Save the California Sea Otter flyer (which may be a reference to Seth's spirit animal) is run by the Friends Aligned To Save Others, aka "FATSO".
Kaitlin, Frank and the child are wearing "Team Julie" T-shirts, just like the "Team Bullit" T-shirt Kaitlin wore in the episode "The Case of the Franks".
Taylor's date of birth is February 8, 1988.
When Taylor is placed onto the Terrorist Watch list at the airport, she is described on the computer screen as:
Deceptively innocent in appearance. Known associates wanted for questioning. Mexico law enforcement may have further info on incident in that country in 2006.
The church Julie is supposed to get married in, before they take the wedding to Berkeley, is the same place she married Caleb and the same place his funeral was held. It has appeared in both the first and second season finales.
Ryan and Seth hug for the second time ever during this episode. The only other time throughout all four seasons is when Ryan was leaving in The Pilot.
Kirsten gives birth to a girl and she and Sandy name her Sophie Rose Cohen.
When Taylor meets Summer in the arrival room, there's a man with a sign saying "Schwartz", which is a referral to Josh Schwartz, creator of The O.C.
Goof: In the hospital scene with Ryan and Seth, right after Ryan says that he was kidding about the sudden urge to read comic books, you can hear Seth talking, but his lips are not moving.
When Seth offers the Range Rover to the homeless guy in exchange for the caddy, he mentions that the axle might be broken.
In Series 1 - The Escape, when the four make their trip to Mexico, the axle also breaks and they have to spend the night in a shabby motel.
In this episode, we find out that Julie used to sing "Night Moves" to Kaitlin when she was a child. In the Season 1 episode "The Heartbreak," the same song was playing in the background when Julie and Luke began their affair. The song also plays in Luke's car after he sees Caleb propose to Julie in "The Proposal".
"91" was shown on the birthday cake (with a 9 candle and a 1 candle) in the Ice Cream shop when Julie and Kaitlin were singing "Night Moves." This is in reference to the episode number: "The Night Moves" is the 91st episode of The O.C.
When the Cohens return to their house after the earthquake, the exterior of the house was from season one, because Sandy's BMW is in the driveway which he hasn't driven since season one.
We find out that both Ryan and Seth have O- blood type.
Frank's height and weight are listed at 6'4" 3/4 and 185 lbs.
Taylor's birthday is February 23rd.
The movie Ryan and Taylor are watching is The Hunchback of Notre Dame, featuring Charles Laughton and Maureen O'Hara. It's based on Victor Hugo's novel by the same name.
This episode explains in the Season One finale "The Ties that Bind" when Kirsten tells Sandy she knows what the pregnant Teresa is going through (trying to decide whether to keep the baby or have an abortion). She didn't reveal anymore than that, and this episode reveals that what she meant was that she had gotten pregnant before and had an abortion.