Spoilers contained if you havent started watching the new series so dont read on. LOL if you havent been following then you will have no clue. Alot will be answered in the remaining episodes but here a few recent updates.
SPOILER! SPOILER SPOILER
Lock is dead. He has been dead since Ben murdered him a couple seasons ago. The man or whoever he is, who is in the body of Lock is called Black Shirt. He is Jacobs arch enemy. Jacob is like the God of the island. We dont know who he is exactly but im sure that will be answered soon. Anyway, last series we found out Jacob and Black shirt were living on the island in the 1800s.In the 1800s Jacob and Black Shirt had a conversation. The two obviously disliked each other and disagreed on whether or not The Black Rock's arrival to the island was a good thing. Black Shirt made it clear that he knew Jacob brought the ship and that it was a bad idea because, "They come, fight, they destroy, they corrupt. It always ends the same." Jacob says, "It only ends once. Anything that happens before that is just progress." Black Shirt asks if Jacob knows how much he wants to kill Jacob and Jacob says yes. Black Shirt says that one of these days he'll find a loophole.
Black Shirt couldnt kill Jacob, he needed someone else to do it. Thats the loop hole. Thats why he became Lock, so he could then persuade Ben to kill Jacob. Job done, he got Ben to stab Jacob.
We also found out Black Shirt was infact that black smoke monster on the island.
Saied, died in the last episode. He then came back to life at the very end. I dont know why yet, have to wait till thursday, but im guessing, that Jacob will come back to life in Saieds body.
As for everyone else, seems like there are 2 dimensions now after Juliet blew up the bomb last series. There is the dimension where the plane never crashed and everyone went on living there lives as normal, and the other dimension where they are all still stuck on the island. I personally like this idea as it was great seeing all the characters back in the real world, not knowing each other, dealing with their real life problems.
Anyway im sure that didnt clear up anything and you are still as lost as ever.