I think that it will end with one of two scenarios- 1. Two characters (maybe Aaron & Jack, Charlie Hume & Ji Yeon or anyone else) will be sat on the beach and it will be a replay of the scene between Jacob and the man in black and it will end with like every thing continously looping for ever. Or - 2. Jack or Ben or Sawyer or Sayid will sacrifice themselves to save everyone else from a threat (Like the volcanoe or MIB or Jacob or something) and everyone will be saved and Desmond's vision that he had in Season 3 of Claire & Aaron getting rescued will come true. What are your thoughts ?????????????