So who is Lost's Jacob?

Seriously. This week we were introduced to Jacob, the Being in charge of the Island. The one person who gives Ben his orders.

But he wasn't really there. At least, I didn't see him.

SPOILER SPACE for those who don't want to speculate as to who (or what) Jacob is.

But after some web surfing today I came across a screencap of the man. One person I came across thought that Jacob was Locke. That to me is an interesting proposition. A future Locke needing to be saved by the current Locke. But Jacob has too much hair. But if you look closely at him, it looks a bit like Jack's father, Christian.

So the speculation continues.

Here's the Jacob page on lostpedia which is insightful regarding the man behind the curtain.