I bet the wreckage footage was shot way back at the beginning of season one.
That is what I thought, it was kind of a homage to the pilot. If the wreckage was shown pre "LOST" symbol it would probably mean something which it wasn't.
You know the more I think about Lost's ending I think it was almost perfect, I mean it was brilliantly written and directed. It wrapped up the lives of all the characters we cared most about.
About the mysteries, I'll admit I was disappointed some weren't wrapped up, but you know it was smart. Lost will live on for years to come with people debating the clues in the show and coming to their own conclusions. For example with the smoke monster, did anyone else notice the skeletons in the cavern with the light?What was their meaning, could they have been previous vessels for the smoke monster?
I loved how the creators made the analogy Jacob gave Richard of what the island was keeping contained with a cork, turns out it was a mystical cork. Hilarious stuff.