Okay, I am busting with all kinds of theories and I'll try to organize them but I feel like I'm really on to something here.
First off. Heroes is a joke. This is the best show I've ever seen.
Now, my first point:
1. Where does Lost pickup next year? In the present day (Jack and Kate off the Island) or back on the Island 3 years ago (which is when they are there really). Or does it pickup at this future time like in the final season and finish from there?
Battlestar Galactica last season ended by jumping 1.5 years into the future and then picked up.
Lost could start IN the future, where Jack and Kate left it at the Airport, and the flashbacks next season will be TO WHAT HAPPENED to everyone after that phone call.
Fraking Brilliant!
Now, my theories on what is going on and stuffs:
Obviously this season has been a lot about time. Lost Time, etc.
The biggest clue out there: Locke says "You weren't supposed to do this Jack."
Somewhere along the timeline after the plane crashed, something changed. Who knows why? Someone ELSE was either supposed to make that phone call, or stop that call from being made. Locke tried to stop it, but I guess he just couldn't kill Jack and had to let it happen. So Jack made a phone call that he was NEVER supposed to make.
Which sets in motion events that never should have happened.
Then in the future, even Jack says "We weren't supposed to leave."
Something horrible happened.
There is a lot of stuff about time travel and things that weren't supposed to happen.
Libby being on the plane is another thing. I think she was on that plane for a reason, because she knew it would crash. Someone sent her maybe? Maybe she was supposed to do something? Maybe something she already did that I forgot, was important.
And I strongly believe that Locke is Jacob and the entire time Ben has been listening to Jacob, it's really Locke from the future. Perhaps...OMG, perhaps Jacob himself told Ben to go get Locke's dad so he could kill him, and change the course of time and become who he needed to be to save the people there. Jacob is using Ben to help mold Locke into something he should have been. That's why there was so much made out of Locke needing to kill his dad.
Something happened though...something messed with the plans that were in motion. Jacob blocks all communications off the Island so that ship could never arrive or be called...but Desmond perhaps...is the difference? He ended that blocking, which screws everything up.
Okay, a few other random tidbits:
Of course Charlie locked the door, because if he hadn't, the whole place would have flooded and Desmond would have died. He saved his life.
Secondly, I think the two skeletons in the cave...from the very beginning...will be two people who we already know, who crashed on that plane.
It's just starting to all fit together for me...my head is spinning...I think i see where this is going.