some more things i found...

The producers want to explore what happened to Desmond in prison; how he ended up there, and why they want him back.

Ben was caught accidentally by Danielle's trap and we will find out why.
We will learn why Ben was travelling across the island and why he ended up in Danielle's trap.
Ben and the real Henry Gale "had words".
We have not seen Ben's motivation for his role in the purge, but we will.
Quote from Michael Emerson: "We have a mess of new characters that I think the audience will be intrigued by. I can say they are characters that are ambiguous. Some of them have extraordinary powers, and some of them are very dangerous." <-- what sort of powers??

Quote from Damon Lindelof: "Jacob? The answer lies further downstream in the ongoing story. (longer pause). Character names on the show are not assigned without a reason. And yes, that is a clue."
Quote from Carlton Cuse: "Yes, we do know how Jacob will be depicted. Notice the careful wording of my answer. And no, Jacob did not appear before he was met by Locke."

Ben uses the volcanic ash circle to contain Jacob. Jacob also has the means to control Ben to an extent.  <-- So that's what it is

The theory that Libby was Dharma is NOT "barking up the wrong tree"  <-- Remember that thread

The four-toed statue is very important and will be addressed in season 4.

The volcano on the island will be of "seismic importance" (pun very much intended.)

The whole deal with the monster will be definitely answered.

found it here

http://lostpedia.com/wiki/Season_4/spoilers

there are alot more...i just posted the ones i found interesting. it actually has a sort of synopsis of all the upcoming episodes...i didnt read them all though...i was afraid they would be true and it would ruin it for me.

This is more a theory based off of the spoilers.

Do you think Annie is Libby based off of these facts.

Lindelof: There's really one significant missing piece to Libby's story. How did she get from A to B — from Desmond to the mental institution? We know the answer to that question, but the only way to tell that story is through another character's flashback, and that character would have to be another character on the show who is not among the beach dwellers.

and also what gf stated

The theory that Libby was Dharma is NOT "barking up the wrong tree"

Also I found these pics online one is of Annie as a child and the other is of Libby at the institution.

Thanks for the rep and posting in the other thread wasnt sure what to post without giving away spoilers.