Deliberate mistake: As the Wraith "stun bomb" activates at the SGC and everyone falls to the ground, it is visible how everyone uses their arms to dampen the fall.
Factual error: Anytime a character fires a missile at an airborne target, it's invariably from an M136 antitank launcher. The M136 is designed to hit relatively slow moving ground vehicles and is useless against fast moving airborne targets. (This is because used M136 tubes can't be reloaded and are very cheap to use as props).
Maj. John Sheppard: "Get as far away from the nuclear explosion as possible." That's good advice, Rodney, thanks.
Trivia: In the final episode, 'Enemy at the gates' Sam Carter says that the new ship is to be named the General George Hammond in memory of the character Hammond who had died of a heart attack. This is a tribute to Don S. Davies, who played Hammond, who sadly died of a heart attack in June 2008, shortly after filming Stargate Continium.
Question: When the ancients return to Atlantis they are greeted by 2 star general O'Neill but later in that episode and the part 2 episode he only had one star on his uniform. This same thing happened in a SG-1 episode when Dr. Jackson became a prior for the Ori.