(Possible) MAJOR SPOILERS!!!!!
If something a lot of people are saying on imdb is true, this is the ending......(possibly)
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It turns out that Fd5 is set before the original Final Destination, and at the end, the remaining 2 or 3 chars get on a plane....which turns out to be Flight 180! The main characters don't find out about Alex's panic and premonition until everyone form the original has been escorted off, and they realize they're screwed as they take off and Flight 180 explodes...!
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If that IS the ending, even though it does the "everyone dies" gimmick again, that is quite possibly the best way to have done it.