After season Premiere, I started thinking that the Oceanic Flight we saw it is not the one we know.
There will be another flight. The Oceanic 815, that will crash again, but in the see, and everyone will be rescued and saved.
Why?
Cause the coffin is not on the plain, like Shannon, like other people of the tailsection...
...and because Locke told us that an Airplane with a good Pilot can land on the ocean safely!
...and because now there is no more Island: is underwater.
So I think the flight we saw it's not 815.
They will realise all during the show and organize a new flight of 815 at the ending of the show, while on the alternate timeline on the Island, they will probably die (Richard told us).
Sorry for my English,
Airbrusher