Revealing mistake: In reality Deborah Messing is pregnant but her character is definitely not, so Grace has been filmed lately hiding behind big purses, pillows, counter tops, coats, etc. For some reason in this episode there was some rather sloppy shooting where Grace's waistline is concerned: When she and Karen are first entering the cabin, right after Grace says the line '...driving past 20 churches...' she turns sideways and for a few seconds there is a clear shot of her advanced pregnancy. Additionally, when Grace and Karen go to bed (also in the cabin) they have Grace lying on her back so the pregnancy is quite obvious in that scene, too.
Continuity mistake: When Grace and Karen enter the cabin, Grace puts her bag down on top of the sofa, so that the large bottom faces the door. In the next shot when she walks back over the bag has now changed position so that the bottom of the bag faces us.