Continuity mistake: As Trent and Lionel talk, while Lionel is in the hospital bed, when the camera is behind Trent his shoulder and neck are barely illuminated and is in shadow as the camera is looking down on Lionel. When the camera is looking up at Trent, even though he has not moved, his shoulder and neck are now brightly lit and shows no sign of a shadow.
Continuity mistake: As Lana and Lex are talking, as Lana says "Actually, umm, I came by because.". In the middle of her going "umm" there is a camera change. Before the change Lana has her right hand on the arm of the seat. After the change she now has her right hand scratching her head.
Continuity mistake: During much of the conversation between Clark and Lana, while in the caves, you can see the cave painting that matches the tattoo on Lana's back is behind her. Then, towards the end of the conversation, she is still standing in front of Clark and during the scene has not moved from that position yet, once she sees the cave painting behind Clark she walks over to it and turns around to face Clark, which puts the painting behind her even though it was already behind her before she moved.