"Lost" Production Mistake Or Clue About "Him"?

ABC has released today promotional images from last night's fall finale of "Lost".

In the heart-pounding climax of the episode, Jack cuts Ben's kidney on purpose while performing a spine tumor removal surgery. He then blackmails The Others into giving him a walkie talkie and gets in touch with emotionally distraught Kate who is about to witness brutal execution of her beloved Sawyer. Jack tells Kate she has one hour to run.

What we did not see in the episode, and it is clearly visible in these images, is that the surgery was being observed by an unknown person behind the glass window on the OR door.


If you look closely at the second image below this text, you will also see the weak reflection of this man/woman in the glass.

Who is that? Is it Jacob, the man Pickett referred to while leaving the OR to murder Sawyer? And if so, is that "him" that Desmond and Ben referred to in Season 2? Is it the Grand Leader of Others?

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