Melissa Fumero (Amy Santiago) is visibly pregnant. In an attempt to obscure her pregnancy, she carries the same bag in nearly every scene. Her baby bump is visible when Amy and Jake enter the hallway in their cruise tourist disguise.
Even though the cruise that Jake and Amy take is shown to be underway and out on the open water, the scenes set on the cruise ship were actually filmed on location on the Queen Mary, a 1930s Cunard-White Star ocean liner that is permanently moored at a dock in Long Beach Harbor as a tourist attraction featuring restaurants, historical displays, event spaces, and a hotel. Its proximity to Los Angeles makes it a common filming location for movies and TV shows that have scenes set on period ships; TV shows such as Castle (2009), Entourage (2004), The X-Files (1993), Murder, She Wrote (1984), CSI: Miami (2002), and NCIS: Los Angeles (2009) have all used the Queen Mary to serve as a ship location.
The cruise ship shown in the external shot approx 6min is a Voyager-Class ship (the Adventure of the Seas) operated by Royal Caribbean International.
Amy tells Jake that she loves him for the first time while they are Salsa Dancing. One of the first romantic moments Jake and Amy have is in Season 1, Episode 22: Charges and Specs, when Jake teaches Amy how to salsa dance while they're working a case.
Jake Peralta referenced Jimmy Buffett right after the song "Escape (The Piña Colada Song)" by Rupert Holmes played. "Escape (The Piña Colada Song)" is commonly misattributed to Buffett.