Continuity mistake: Much to the photographer's dismay, Kate's husband receives a 'very important call' when they are posing at the beginning of the movie. The photographer's right hand is horizontal on the lens during his reaction shot, but he had it vertical on the camera body before the cut. (00:01:20)
Continuity mistake: Second part of the conversation when Emma right away spills the 'secret' to Lissy; forgetting the fact that they both have refills for their drink (we just assume they had one off-camera not shown), the wine in Lissy's glass changes level from shot to shot several times (for instance when she listens to Emma once she answered about the dead guy it empties in mid-air, or when she suggests to "do it at work", the glass is refilled in the reverse shot). (00:23:50)
Continuity mistake: Amy throws her shoe at Jo for leaving her at home while she and Meg go to the theatre. She picks it up, but in the next shot, she is no longer holding anything. (00:45:43)