Visible crew/equipment: Right before the wedding Michelle is talking to Jim's father about her vows. Behind them on a table there is a mirror and you can see the arm of a crew member reflected in it several times. (01:21:35)
Continuity mistake: In the final scene, in the bathtub with Stifler's Mom, the amount of soap bubbles on Finch's head changes between shots. (01:33:40)
Continuity mistake: In the beginning, when Michelle goes underneath the table at the restaurant, Jim knocks the phone over to the middle of the table. Later on, when Jim's dad comes in, the phone is back on the end of the table without anyone touching it. (00:01:35 - 00:02:30)
Continuity mistake: In the first scene of the movie, when Jim and Michelle are in the restaurant, they show Michelle with her napkin folded flat on her lap. Later when Jim tries to get Michelle to find the ring the napkin is back on the table folded in the formal restaurant triangle. (00:00:30 - 00:01:15)
Continuity mistake: When Stifler has the "truffle" in his mouth, there is none over his teeth. Then there is loads all over his teeth instantly. (01:07:15)
Continuity mistake: When Stifler realizes that Jim is getting married, he has some cream on his face from the cake. In the next shot most of the cream is gone. (00:14:45)
Continuity mistake: When they are looking at flowers, Michelle's mother picks up some flowers and says, "Sahara and desert rose for your bridesmaid's bouquet," you can see one of the flowers change color in the following shot. (00:35:10)
Continuity mistake: In the dog sex scene, the little white dog is on Jim's leg. The camera cuts and now it's gone. (00:11:10)
Continuity mistake: When Jim, Finch and Kevin are talking in the bar near the start, the amount of beer in Jim's glass always changes. (00:14:20)
Answer: As I remember, there was a scene where someone says, "Michelle's parents are flying in for the wedding."