I think it's possible that Jin is alive and still on the island. Jack
has been telling a lie about what really happened, so it's possible
Jin's death has been re****ted to help cover up the existence of the
island.
As for Sun's and Hurley's sadness at the cemetery, perhaps they too
are playing a role because they are being watched by Widmore's or
Paik's people.
Something just doesn't ring true about this. It smells of a red
herring. Even the preview for next week's episode, where we're told
someone is going to die, doesn't convince me. Lost isn't known for
giving things away that easily.
Of course, I could be completely off base. Guess we'll find out soon
enough.
Todd