When Teal'c and Jack are living the mission over and over again, two of the other soldiers are carrying M4A1 assault rifles. Jack said that the mission happened in 1982 but M4A1 assault rifles were not made until 1994.
When Colonel Michaels is looking through his binoculars before the first assault on the house there is a sign behind him reading "Schloss" (German for "castle"). It should read "Schloß" as the mission happened in 1982 before the German spelling reform of 1996 when the spelling was changed from "Schloß" to "Schloss."
Don S. Davis clearly says "tacknology" instead of "technology" during the fake debriefing.
During the series pilot, Kawalsky mentions that he went to Abydos with Jack and never knew Jack had a son, but we learn in this episode that they've been on other missions together and that they were buddies prior to their Stargate involvement. It's unlikely that Jack never talked to Kawalsky about his family.
When SG-1 is in the virtual isolation room, Jack calls the planet PJ7-989 instead of P7J-989.
When Teal'c and Jack are "falling back" from the melee, you can see Kawalsky behind them, but at the last moment, he falls over sideways, clearly on purpose (if he'd run a little bit more, he would have been obscured by the wall, and he would have appeared to "disappear")
In the film, they said Daniel's parents died in a plane crash, and in this episode, they died in an accident in the museum. (Note: there is some speculation that the parents referenced in the movie were his foster parents and it would make sense, but it has never been officially confirmed.)
At the beginning, you can hear someone say "Chevron 4 encoded", but the 3rd chevron on the gate lit up.
Jack: General, without meaning, this time, to sound like a smartass, are you cracked?
(SG-1 pops out the Gate in the middle of a beautiful garden)
Sam: This is beautiful.
Jack: Yeah... but where there's a garden, there's snakes.
Daniel: And flowers. (sneezes) Way too many flowers.
Gillian Barber, who appears here as one of the Residents, would later play the recurring role of Ambassador/First Minister Dreylock from Jonas' planet Kelowna.
Both the Tin Man and Gamekeeper's planets are given a designation ending in "989", and both consist of moving the team to some form of virtual living.
Robert Duncan would later play the title character in the episode "Seth".
The Gamekeeper character is played by Dwight Schultz, who also played the recurring character Lt. Reginald Barclay on Star Trek: The Next Generation, who had a similar obsession with simulated environments (ie - the holodeck).
Syndication air date: October 4, 1999.