Factual error: In a very early scene, just as the young girl is pulling a cellphone out of her vagina, if you look closely you can see that the "cellphone" she is holding is actually an iPod Nano 5th generation, which does not make phone calls. (00:04:20)
Continuity mistake: When Machete mounts the minigun to the motorcycle in the big fight scene at the end of the movie, it's just the gun barrels and breech on a plate between the handlebars, with no ammo feed. When he's in midair and firing, there is a very visible ammo feed chute going into the side of the gun (as there should be). In the next frame, he lands and gets off the bike, and again it's only the gun/breech assembly, no ammo feed.
Trivia: This is the second time that actor Danny Trejo has played a character named Isador "Machete" Cortez, the first time being in "Spy Kids." It's debatable whether or not they are the same character.