When Bree says, "Hi, Danielle. How was school?", Danielle's jacket is slightly moved, revealing a bit of her sleeveless shirt. In the next shot when Danielle answers, "It was okay," her jacket has moved and covered her shirt.
When Bree gets out of the golf cart to see Rex on the field, she is carrying a pot of urine in her left hand, but in the next shot, of her upper torso and face, her left hand is clutching the strap of her handbag and the pot is now in her right hand.
When John is speaking to Susan about his relationship with Gabrielle, Susan puts her hand on John's cheek, but in the next shot, when John's mother is looking out of her car, Susan can be seen with her hand on John's shoulder.
In the scene where Bree and Lynette are talking about nannies, Lynette is in the back seat strapping her baby daughter into the car seat. In the shot facing Bree, Lynette takes a baby toy lying on the back seat and hands it to her daughter, but in the next shot facing Bree, the toy is back on top of the seat where again Lynette hands it to her baby.
When Susan is on the catwalk at Gabrielle's fashion show, Tom announces what she is wearing, but if you look in the background you can see his lips are not moving when he is speaking.
Several days must have passed between the teaser of this episode and the rest of it, since Gabrielle has had time to make up (very professional-looking) cards and posters, gotten several dozen volunteers and reserved dresses for many of them, yet Paul has only just gotten around to disposing of Mrs. Huber's body and trying to wash the blood out of his shirt. Even if we assume the teaser takes place right after the end of the last episode (when Paul murdered her), that's still several days of keeping a rotting corpse and enough evidence to put him away for life around his house.
Mrs. Huber died at the end of the previous episode, "Guilty", so why is she signed up (with dress reserved and everything) for a fundraising idea Gabrielle only had in the teaser of this episode?