Continuity mistake: In the liquor store, Seth kicks a shelf to get lighter fluid. Look closely - it is an overhead kick which means that his foot would be upside down. However Seth's foot is the right way round. (00:07:45)
Revealing mistake: Shortly after passing the border Seth is talking to Jacob who's supposed to be driving. But the reflection in his glasses shows that they don't move.
Continuity mistake: In the opening scene, the pages change in the magazine that the convenience store clerk is reading. (00:01:30)
Visible crew/equipment: During the scene where the Geckos first enter the Titty Twister, right after the shot where Seth takes the bottle of whiskey and glasses from the bar the camera cuts between shots of the bar, right after the band finishes the song a camera is visible in the lower right corner. (00:50:25)
Continuity mistake: Right after Salma's dance, Chet, the bartender and another big guy walk up to Seth and Richie and accuse them of kicking him and breaking Chet's nose earlier. One of Chet's men then stabs Richie's hand as Seth pulls out his revolver and shoots one of the other men. It is obvious and easy to tell that the bullets supposedly hitting the men aren't causing any kind of blood or damage, etc. In fact, it almost seems they are blanks.
Continuity mistake: The scene where the vampires in the Titty Twister bar start devouring the customers. George Clooney confronts Salma Hayek. She taunts him and he shoots her. When he does this the jacket falls open to show he is wearing a white shirt underneath. However, when she comes back to life a couple of seconds later and punches him to the ground, his jacket falls open again - only this time it is a completely black shirt underneath.
Continuity mistake: At the end when Seth drives away, we see Kate holding a bunch of money in both hands. The camera angle changes and now both hands are her hips, no money in hand as she walks away. In fact we see no money on her in any way. Where did the money go?
Continuity mistake: As Santanico begins her dance, she swirls her cape. On the third "swirl" a snake appears. The camera shot goes to behind her and the snake's head is working its way up her back. Then in the next shot, the snake's head is round the front and works its way upwards towards her head. (00:55:20)
Continuity mistake: When Richard bends down to pick up the keys in the motel room, we get a shot of Kate's painted toes. Later in the RV, her toes aren't painted.
Revealing mistake: When the gas station clerk jumps up from the floor, you can see the protective clothes he's wearing to protect him from the fire.
Revealing mistake: In the scene where Kate is aiming her gun at Scott while he is being seized by several vampires, it is clearly a dummy surrounded by other dummies when the shot is made and the group explodes.
Other mistake: This mistake is actually about the DVD box art. On the cover, George Clooney is pointing his revolver outwards. A revolver has rear and front sights, but if you look at the front of the barrel of the revolver you will see the rear sights and front sights both there. The rear sights are supposed to be on the backside of the revolver, but on the cover the rear sights are actually in front of the front sights. No revolver works like that.
Deliberate mistake: The disco ball doesn't start reflecting the sunrise until after the lead characters get out, even though it should have began to reflect light right when the door opened.