These thoughts are related to my "Rules Of LOST", explained way back here in the context of the Season 3 Finale:
#1) Most things are simpler than you might think.
#2) Nothing is going to happen as fast as you want (or hope)
#3) The writers/creators are always going to leave some wiggle room.
I'm going to add a fourth rule as well:
#4) Nothing is quite as easy as it seems.
- Does the flash forward work?
- What's up with Jack in the future?
- The baby, the baby!
- Circumstances around the departure
- Why the coverup?
Does the flash forward work?
Yes, definitely yes. I talked in the post referenced above about how LOST really expands the bounds of "what is the story here?". The flash forward has shown that when people get off the island, the story isn't over. LOST has forced that "the story isn't over" fact with only having the Oceanic Six get off the island but the point is there.
Another interesting point with the flash forward is it makes you ask "how in the world does the story get *there*?". This is huge in retaining interest and making it fresh. So, the flash forward definitely works.
What's up with Jack in the future?
I'm not talking about the Jack we saw at the end of Season 3, the drunk, repentant, "we must go back to the island" Jack. I'm talking about the Jack we see in these flash forwards, the Jack who is content to lie through his teeth about what happened on the island, to leave whoever is on the island on the island, and to not give a flying fig about both those facts.
This is the same Jack who said in season 3 "I'm going to get all my people off this island. All of them!". What happened to Jack to make it okay with him that only a few people get off the island, and that he's willing to perjure himself as well? We know it's not the case that all the LOSTies are dead, because Hurley is asked if "they" are still alive and Jack ends up believing that the Oceanic Six has to go back.
This, to me, is one of the most interesting questions raised this season and the one that the LOST crew will have to work hard to justify. (Non-bearded) Jack in the future doesn't feel like Island Jack at all. And yet, there he is.
The baby, the baby!
In the future, Kate's baby is baby Aaron. Claire's baby. So, how did Kate get him? The easy answer is that Claire is dead. But that's too easy. A more complicated answer is that Claire gave Kate the baby for one reason or another, in something like a "burning building" scenario.
I can envision a scene where things get all insane on the island, some people are getting off and some aren't, and Claire (thinking she's not going to survive) gives Aaron to Kate with the promise to raise him and keep him safe. Then, of course, Claire survives. Instant conflict. And, a lead-in to the next big topic.
Circumstances around the departure
The Oceanic Six and Ben are off the island. We can assume many LOSTies are still on the island. We don't know anything about the freighties yet. The LOSTies, except for Hurley, aren't too interested in going back to the island.
The circumstances of the Oceanic Six's departure off the island are going to have to be high-stakes enough that all the odd situations and conflicts are set up or resolved. This is, in my opinion, the big thing for Season 4 and probably how the Season will end. The Oceanic Six will get off the island, but we will know that many other LOSTies are still on the island and in danger.
Season 5 would then be the realization that the Oceanic Six need to get back to the island (so the flash forwards would be mainly from Season 5 events), and Season 6 would be what happens once they do get back to the island.
But the departure circumstances are just rife for speculation. I'm predicting the departure is something big, chaotic and messy along the lines of the initial plane crash for craziness and insanity.
Why the coverup?
Someone doesn't want this island to be found, so much that they drowned a plane full of people in a trench off the coast of Indonesia. That someone is linked to Oceanic, and Mr. Abbadon (who hired Naomi and the freighties), and maybe to Dharma, and maybe to Penny Widmore. And they're playing for high stakes, because you don't drown a plane full of people just for fun. Another interesting question.