More detailed footage
2nd January 2012 Update:
The video seems to show a group of six or eight clustered irregular-shaped lights that apparently fixed in one position. It is getting mixed conclusions ranging from a hoax to real flying saucer, from reflection inside the plane to lights on the ground.
The light cluster of the UFO does not move relative to the airplane but stays stationary in the sky. The UFO cannot be a known aircraft nearby because it flies similar speed and altitude near the plane.
Mr Ruiz moves his hand toward and around the window to show that the image is not coming from the reflection within the cabin. However, several observers think that his hand only blocks reflections coming from the left side of the window and does not block the reflections coming from above and behind, which is the location of the cabin lights.
Some also notice the disappearance of lights in the video. They say that it is because a passenger or airline attendant passed behind the cameraman and in front of the cabin light being reflected.
Mr Ruiz posted a note on his video saying that the copy of the video is already in the hands of Federal Aviation Administration (FAA) for further review.