The "Lost" finale is just nine days away. I watched "Across the Sea" last night and I have some spoilery stuff to say about it, so if you haven't seen it, don't read the rest of this post.
Last chance to run away if you haven't watched the episode...
Some people really hated this episode. I liked it, even though it partially demystified the show. Some things didn't make sense, like how ancient Romans reached an Island in the South Pacific Ocean (though, since it moves all the time, maybe it was in the Mediterranean Sea all those years ago). I'd also like to know how Jacob and MIB's adoptive mother reached the island and why she thinks people are bad, but I can fill in the blanks with my imagination.
My main conclusion from this episode was that nothing will really happen if Smokey will leave the island. Yes, he'd be able to kill people in a larger, more populated area, but it wouldn't be the end of the world (literally). It seems to me that Mother (Allison Janney) was just paranoid or just didn't want her son to leave her. It could very well be that she was not only Jacob's immediate predeccesor, but the only one. She could have been the first one to discover the Island's powers, and she misunderstood it and decided for herself that the place needs to be protected.
I also have a theory about how she got her own powers - not aging, being able to forbid Jacob and MIB to kill each other and being able to torch the village and kill everyone. Maybe she went into that ridiculous-looking cave of light and was affected by it. Unlike MIB, who was knocked out cold when he was swept into the cave, she could run away before it totally consumed her. That's why she was still in her original human body, despite having all these powers.
Anyway, we'll see if I'm on the right track in the last three and a half hours of "Lost" left.