When Tracy comes up from below deck in the "True Love" flashback scene, she is wearing blue tennis shoes. Although the dialogue is continuous, she is barefoot in the very next shot, then the shoes appear again, though we never see her take them off (or on).
When George takes Tracy, who's obviously had too much to drink, into the blue walled room during the party to lie down on the couch, before she gets there, a boom mic is visible at the top of the screen.
Boom barely drops into the top of the frame for a split second, but the shadow clearly travels across the wall when George takes Tracy into the conservatory to lie down after she drunkenly sings that she's "Sensational".
In the "Did You Evah" sequence the boys walk out of the library, wait a few beats and come marching back in to the bar. When Connor picks up the champagne, it still has the cork in place. But Connor immediately pours, without removing the cork/ the cork has magically disappeared.
In the confrontation between Tracy Lord, George Kittridge, and Mike Connor, Tracy is in the center with George stage left and Mike stage right. She turns to face George, which puts Mike behind her. But when she speaks to Mike, she glances left, not behind her. When the camera angle changes a second later, Mike has not moved, but Tracy is now facing him, with George now behind her.
When her mother breaks the news about Spy magazine coming to her wedding, Tracy is telling her mother she really thinks her mother is sorry she ever let her father go. She drops her arms to her side and turns her back completely on her mother, her arms swinging. In the reverse angle, she is only half turned and her hands are coming up to her hips.
After Tracy introduces George to Mike and Liz, George pours drinks for everybody. From one shot to another, Dexter-Haven's drink appears in his hand without his picking it up. Mike picks up his drink twice. Margaret's drink also appears in her hand without her picking it up.