Continuity mistake: The German Feldwebel, who gets beaten to death with a baseball bat, has a badge over his left breast pocket which disappears and reappears during shots. (00:31:30)
Continuity mistake: In the final scene between Brad Pitt and the Nazi officer before he carves the swastika into the German's forehead, Pitts' tie changes three times. First scene it is on both sides of his neck. Second scene it has disappeared from the right side, and the third scene, it is back completely around his neck again.
Continuity mistake: Shosanna is dropping the letters onto the ground while talking to Zoller. In the last two or three high angle shots before she descends the ladder, they're suddenly positioned differently from how they were before.
Continuity mistake: When Bridget von Hammersmark is in the pub, and the SS Officers are offering them a 33-year-old whiskey, you can see that the beer foam in the glass on the table is changing between the shots.
Continuity mistake: In the scene in which Colonel Landa and Shosanna are talking in the cafe, Landa orders an espresso for himself, along with a glass of milk for Shosanna and two strudels. When the order arrives on a tray, the cup of espresso is seen briefly in one shot. The film then cuts to a close-up of the tray, and the espresso has disappeared, despite no-one having put it down. In the next shot of the table, the espresso has appeared beside Landa. (00:50:05)
Continuity mistake: At the very start we see the farmer's daughter hanging a sheet out on the washing line. In one shot the sheet is crumpled with no peg on it and in the next shot it's not crumpled and pegged to the line. (00:02:10)
Chosen answer: It is explained shortly afterwards that a real German would hold up his thumb, index and middle fingers to indicate three. Since, the major already suspects the Captain of being a spy, holding up his index, middle and ring fingers to indicate three confirms this.
Xofer