Here's another opening seen for season six.
You see a closed eye and with the trade make "flashing noise" the eye opens. Camara pans out and you see it's Jake and he's on a plane. You here a voice saying "ladies and gentelmen welcome aboard ocianic air flight 815. My name is Cindy I'll be you flight addendent. Please fasten your safety belt make sure your seat backs and tray tables are in there full and upright possition as we are preparing for take off."
Everything seems to be the same as before. Cindy walks the cabin of the plane handing out drinks to all our losties. Charlie gets up to head to the bathroom (to take his drugs) Cindy alerts the rest of the cabin crew they all head to the front of the plane after Charlie. Charlie bumps into Jack, Rose says "he must be in a hurry." Cindy then sneaks past the other cabin crew members as they knock on the bathroom door. She picks up the phone by the cockpit door and says yes captain, it's Cindy would you felas like your coffee now" she hangs up the phone and turns to the serving cart were she preps two coffees then looks over her shoulder to her coworkers knocking on the bathroom door. Seeing they are not looking she poors an orange liquid into both coffees. Then she enters the cockpit. A minute or so pases before she opens the door again and continues helping her coworker with Charlie. A short while passes then the plane shutters. Jack turns to Rose "don't worrie, this is normal" Then the plane dives wildly then climbs only to dive once more then the turbulance tears the plane apart. Thud cut to LOST Cindy is and always was an "other" planted on the plane (like Micheal on the freighter) to ensure it gets to the island. In the original crash she did give Kate an orange drink similar to that Juliet was giving to be knocked out for the sub ride. Maybe she gave everyone the "knockout juice" or just the ones who were meant to survive the crash and needed in the master plan. This is "course correction" at it's core. The variable is Desmond he'll not be pushing a button in the swan because the "incident" never happened. But he's still on the island. Because the incident had nothing to do with bringing him to the island. From this point anything is possible. Desmond might have simply found the empty hatch (because the purge still killed dharma maybe even Calvin this time) and made it his home until the losties came knocking. The losties would still flash through time as they did in season 5. But instead of trying to stop the incident in 1977 they aim to cause it. Not knowing what crashed their plane they think it was something in the hatch. They try to change the past by blowing up the hatch. They cause the incident. Dharma finishes the hatch and begins pushing the button (to save the world). The losties flash at the moment the incident happens. Starting the circle anew. But this time Cindy doesn't drug the captain, Desmond is stuck pushing the button because of the incident. Then one day in September 2004 he doesn't push the button in time, the magnetic force brings down flight 815. The "circle" is complete. Thus the losties are "lost" in a perpetual loop. Just a thought and a very long one, if you've read this far thank you :P It's just a theory nothing more.