LOST (FINALE)

Already I'm seeing a ton of different interpretations, so here is what I agree happened...

The specific story we are presented in the alternate time-line (or purgatory) starts right after Jack dies, the opening shot of the season was a camera going through the clouds focusing in on Jack, presumably right after he has crossed over from life to death.

Everything on the Island was real, it all happened, Jack and the others did not die for nothing as the MIB needed to be destroyed as he would not rest until the island was at the bottom of the ocean, and in order to make him mortal the light needed to be put out long enough for him to be killed. Desmond accomplished that part of the mission, Kate delivered the killing stroke to MIB, and jack re-established the light for Hurley to protect fulfilling his destiny knowing it would cost him his life... And the last we see of this island story is Jack's eye closing just as the series had started.

Hurley was now the new Jacob, Ben had taken over the role of Richard even though he didn't seem to have inherited Richard's immortality. At some point Hurley and Ben find a way to get Desmond off of the Island and back to Penny and Charlie seeing as Hurley was going to run things under different rules as Ben suggested.

Kate, Sawyer, Lepidus, Miles and Claire all presumably get off safely. Claire most likely returns to her mother and raises Aaron as she is supposed to. Perhaps Kate takes the role of mother for Ji Yeon, but doubtful. Some will probably like to think Miles and Sawyer partnered up on some venture together, and Frank finally got back to being a not so drunk pilot and a B character in the LOST universe.

The alternate time-line (purgatory or whatever) was a place without time, a place of final purification to prep our Losties for their final destination, and to be prepped for that final destination they needed to let go of all of the emotional baggage they had in their lives, be at peace, and remember everyone from the island so ll of our Losties were regardless of when they died in the temporal world. As Jack's father says, everyone dies eventually. In Jack's mind and in the mind of the viewer this is happening right after his death when in fact these events we are seeing in the alternate time-line must be happening sometime after all of our Losties have died which could be decades later, and they are going to move on to Heaven together as a group because of that strong bond they formed on the island. Some people are not ready to move on yet such as Ben whose sins may have been too numerous and had more loose ends that needed tying, but it is implied that he will move on when he is ready. Ana Lucia Cortez, Richard Alpert, Mr. Eko, Charles Widmore, Daniel Widmore, Eloise Hawking, Michael Dawson, Walt Lloyd, Danielle Rousseau, Alex Rousseau and further dead or unseen company aren't a part of this main LOSTIE exodus for other reasons.

So what was the deal with Desmond?

The same thing that has been going on with him the whole time, he is seeing the future; so far into the future that he sees past this life and into the next one. Desmond should have died when he turned that key, but he didn't and with it came a certain uniqueness that allows his consciousness to travel through time to the point where he can manipulate events in the past present and future, and in this case he is manipulating the farthest point of his future which is his afterlife and the afterlives of all of our Losties by helping them to move on. Now the mystic knowledge he possesses in the alternate time-line is not really explained, but it can be believed or presumed that it is a form of divine revelation of sorts, that in death things are made clear to him when he has recollections in these experiences with the Losties.

What happens to the dynamic duo of Hurley and Ben? And what happens to those who left on the plane? No one knows for sure, and it is left to us to speculate how they ran the course of their lives but in the end they are all reunited, they all learn to let go, and they are ready to move on.

The End.