Revealing mistake: When Miranda comes home from work and takes off her black jacket, her black dress underneath is tight. You can tell how pregnant Cynthia Nixon is when she lies on the bed with Steve. (00:08:05)
Visible crew/equipment: Sam says "this party's gonna be amazing, A-list" and a black shade used for lighting is reflected on her sunglasses. (00:09:27)
Revealing mistake: When Carrie and Berger are talking on the grass, Berger suddenly gets up to leave. He grabs his jacket which Carrie is sitting on, knocking her over. As she falls back, you can see her quickly pull the front of her shirt over herself to make sure it covers her pregnant belly. Also, as Carrie starts to get up, there is a point where her shirt falls forward, and you can see Sarah Jessica Parker's pregnant bulge from the side. (00:18:35)
Revealing mistake: During this scene, Samantha throws a cantaloupe through the window. As Sarah Jessica Parker reacts to the incident, you can see her very pregnant belly from the side, especially as she bends over. According to the commentary, she was about 7 months pregnant at the time. (00:20:15)
Continuity mistake: During brunch outside, Miranda's bite on her muffin changes shape between the side and the front shot.
Continuity mistake: During the girls' chit-chat, the amount of ice tea in Miranda's glass suddenly decreases between shots.
Continuity mistake: While eating outside with Miranda and her baby, Carrie takes a french fry to her mouth, but her hand suddenly disappears in the following shot.
Answer: A popular brand of sexual lubricant. See http://www.k-y.com/index.jsp.
J I Cohen