Detective John Sheppard has the same poster of Johnny Cash on the wall of his office area as is on the wall of Sheppard's bedroom in Atlantis.
Woolsey (played by Robert Picardo) mentions sadly that Star Trek: The Experience - The Klingon Encounter (1998) has closed. Picardo is famous for playing Star Trek: Voyager (1995)'s Emergency Medical Hologram, a character who was the star of one of the Experience's simulator attractions.
Many of the establishing shots of Las Vegas appear to be taken from CSI: Crime Scene Investigation (2000).
The two talkative, 'mobster'-looking men at the poker table are both well known for being on the popular mafia TV show The Sopranos (1999).
This is the only episode of the series to take place entirely on Earth and in the Milky Way galaxy, albeit in an alternate reality.