When Phoebe is holding her cup of tea at the end, the string of the tea bag flips from away from Phoebe to towards her with each scene change.
When Wyatt orbs himself and Piper to Leo, Leo is in a glass case fully in water. After Piper makes the glass explode, only Leo's shirt and head are wet, his pants are completely dry. His entire body should be soaked as he was just submerged in water.
When Piper is rescuing Leo, as she shifts the baby in her arms to blow up the glass the blanket falls off the baby's head and you can see that she is actually holding a doll.
Phoebe asks Paige if there is a vanquishing potion for the Crone in the Book of Shadows. Paige nods and points to a sentence she is reading. However, the close-up of the page reveals three errors: Paige is pointing to a generic sentence that says nothing about defeating the Crone. Another sentence on the page says that a 'high level demonic vanquishing spell' (not a potion) is needed to kill the Crone. And finally, there is no mention of any potion anywhere on the page.
In the attic, Phoebe is standing right behind Piper when the Kazi demon launches himself towards them from behind. Phoebe jumps out of the way but Piper has disappeared from where she was standing.
When the sisters are learning of each other's missing senses Piper is facing Paige on the left and Phoebe on the right. When she walks over to them and the camera switches views Phoebe and Paige have switched places.
When Phoebe first loses her hearing while at the meeting, she talks at a normal volume while leaving the room. During the rest of the time she is deaf, she talks in a very loud voice.