They’re coming!
this was my sisters theory, well my cousins theory but he told her and she told me… anyway. We think that when Jacob gets stabbed in the end and he says they’re coming, he means jack kate hurly sawyer and jin. Like maybe in the end wen juliet “detinates the bomb” (we all think), i think it was another flash bring them all back to, not the airport where they started, but to 2007 with the rest of them. I thought it was a cool idea. I guess we’ll just have to wait till commercials for next season come out to know.
The whole flashing through time thing’s done with the wheel, but if you mean a flash like the one on the plane, perhaps.. Maybe Jacob made a last move to bring them back.. The question is: Why? Why would they be brought back to 07 if Jacob dies? The answer: Jacob takes control of Juliet who wouldn’t survive the flash (due to the effects seen in the flashes in beggining of season 5).
So, maybe we’ll be seeing a Juliet vs Locke showdown next season.