A majority, if not, all of the U.S. East Coast was blacked out by an EMP blast in Modern Warfare 2, and yet all electronics and vehicles in the New York missions are fully functional as if nothing happened. The game takes place right after Modern Warfare 2 and unless either New York was somehow unaffected or recovered from the EMP in an impossibly short amount of time between both games, the effects of the EMP should still be seen in this game.
During the ending cinematic of "Black Tuesday", after downing the jamming tower, radio chatter indicates that F-22 will be flying in with JDAMs but the wire frame outlines of the aircraft are clearly F-15s.
During the London mission several of the SAS soldiers are incorrectly given the rank of "Private". The correct term would be "Trooper".
In any pre-mission cutscenes where we can see helicopters flying, the rotor blades bend downwards - in flight they should be horizontal or bending slightly upwards due to the aerodynamic lift.
During the opening of "Black Tuesday" in addition to the mistake calling the wire frame aircraft F-22s instead of F-15s, the munitions being expended are referred to (and portrayed) as JDAM missiles. The JDAM is, in fact, a guidance system attached to conventional bombs allowing them to be guided via GPS.
Cars can explode and kill NPCs or the Player. Gasoline is not explosive and therefore cars should not explode.
The information about the daughter of president Vorshevsky, is shown in the cinematic before the mission Scorched Earth, where she is called Alena, but she is being called Athena throughout the mission. Athena is given as a codename by the Americans.
The Oscar II submarine is listed as American in the mission briefing when it is Russian. It is designated as American because the objective is to capture it, and at the time of the cutscene wherein it is designated as American, it is shown launching missiles at the Russian fleet while under U.S. command.
In the cut scene before the mission for rescuing Alena, her name is spelled "Vershovsky" on the label above her building.
The Russian submarine is shown firing torpedoes even though there is no target to fire at.
Near the end of Black Tuesday, once you secure the keys from Russian Sailors on the Bridge of the Sub, your Teammate reports to Overlord, and they provide grid coordinates to launch the subs Cruise Missiles against the Russian Fleet. Overlord provides a 6-digit grid, specifying a 100M AOE (Area of Effect). This would not be sufficient data to launch against a fleet of warships, as all those ships don't fit in a 100M grid. This feat would likely require multiple 8-digit grids (10M precision), one JDAM for each ship.
In the New York Mission, it shows many lights and other electronics still working, but the EMP blast from the nuke in Modern Warfare 2 should've shut down the entire eastern seaboard.
In the mission to destroy the jammer in New York City, sirens can be heard in the background. It is likely that all civilian forces including first responders would have been evacuated by the time of the mission.
Captain MacTavish pronounces the 'Z' in 'UAZ' with the American pronunciation. Captain MacTavish is British.