After reading the comments I must say a few things.
1. I agree with most that the things that happened on the Island where real. Only the Side flashes where Limbo.
2. One post mentioned that the final picture of the plane crash gave us no clues, But it did. Right after the crash the survivors piled up all the close in a pile. That pile is in the shot.
3. It is clear that many of them lived longer then others. Not only is it said but Hurley says to Ben, "you where a great number 2" and Ben says "you where a great number 1" if they had not survived this would not have been said. Also Ben waits and does not go with them. He is not part of this group. He is waiting for his group.

All in all it was great. I did not watch the show on T.V. I always watch it on the net and I watched the last 3 episodes one right after the other. I am a former Marine, and played football for 20 years but when Jin and his wife got their memories back in the hospital I wept like a baby. Same for Charlie and Claire. Very touch the way the characters reunited. I felt like I was watching some special.