Continuity mistake: During the operation on the Asian girl from the market, a stitch breaks and Christina is covered with spurting blood, including all over her mask. When she turns to leave the OR, the all-over splatter on her mask has turned to dribble-like streaks instead.
Continuity mistake: When Addison first comes to Seattle, she mentions that she likes Derek's hair. She says it's longer than usual, looks like Russell Crowe. In the flashback of the night he left his hair long like it always is. Actually it seems a little longer in the past than current.