When the interns first meet in the locker room, George puts his stethoscope on twice.
When Izzie and the other interns are awaiting the helicopter on the hospital roof, you can see a corner of her face in a close-up shot that shows her wearing her black glasses. But in the previous and subsequent long shots she is not wearing the glasses.
When Alex Karev is being yelled at by the Chief, and Meredith corrects his diagnosis. One of the nurses, with the red hair appears in two places. She appears standing behind Alex and then behind Meredith in the doorway. It flashes back and forth with the nurse in two places at once.
When Dr. Shepherd asks the interns for help on the Katie Bryce case, Izzie puts her hair up in a clip twice.
When Meredith and Derek are making out in the elevator, some shots, she has patient files still in her hands, and in others, they are dropped on the elevator floor.
Meredith shouldn't have been allowed to approach the patient in just her scrubs because it would contaminate the sterile field. She should have been in a sterile gown and other appropriate sterile attire.
In the pilot episode and in various episodes throughout, thunder is heard to indicate Seattle's famous rainfall. In reality, it rarely ever thunders or storms in Seattle, nor does it downpour as often as depicted on the show.
When Dr. Grey first sees Dr. Sheppard for the first time in the hospital, while she speaks to Dr. Bailey you can see the legs of the cameraman in the glass next to the door.
When Meredith Grey spots Dr. Shephard and realizes her one night stand has already come back to haunt her, the camera man is visible in the glass panel next to her.
When the helicopter lands on top of the building and they are removing the patient from the helicopter, you can see the equipment visible on the right hand side.
When Meredith is asking Dr. Bailey for Derek, a cameraman is reflected in the glass panels beside them.
When we see the chopper approaching Seattle Grace Hospital, the logo on the side of the building reveals the "hospital" is actually a local TV station.
Meredith is shown driving to work on a highway, but if she lives on Queen Anne Hill, she is actually driving towards her home.