Edward Kitsis and Adam Horowitz reveal: Jack is definitely coming back to the beach and will be forced to be a leader once again. There will most likely be one more Jack flashback this season.
Kate is obviously having issues with Juliet being on camp. One because she's an Other and imprisoned her for most of the season, and the other is because Jack seems to be bonding with her. We'll be exploring the quadrangle [formed by Jack, Juliet, Kate, and Sawyer.] Kate's suspicions of Juliet will continue to play out.
Sawyer is going to be getting quite a surprise this season, something that he never thought would happen is about to happen. We're going back to some very core issues that Sawyer has dealt with since the very beginning of the show and the exploration of that should bring him some nice surprises. He will definitely have a very interesting trek with Locke. [We will explore] what's going on with Cooper, what's going on with Locke, what's going on with Locke and the Others and what Locke has been doing since he's been away from camp.
[Charlie] will have a lot of though choices [to make], because it would be easiest and safest to just stay in his tent, but on this island, you know, that's difficult.
[Sayid] will be called to action!
There are some very emotional things going on for [Claire].
Hurley will be playing a central part in the finale.
Sun is going to learn interesting things about what happens to pregnant women on the island and when she does learn these things, it's going to impact her relationship with Jin in a profound way. We will find out that Sun has a secret feat that she is hiding from Jin, and that will not only be voiced, but answered. [During the Jin and Sun flashback,] you will get a taste of them as newlyweds and kind of see where he was before he started to be Mr. Paik's head henchmen.
We will definitely get to understand that Juliet is very conflicted and we will show you why.
[We will explore] what's going on with Penny and Desmond. You know what we started in the finale of season two? We'll continue to explore that.
Plus, there's another big revelation on that front coming up pretty soon. There will be an incident on the island that will pretty much shake what everyone thought about this show...