This may be un-popular here but I think its worth mentioning.
IMHO, and I think a lot of folks would agree, what everyone on the internet is referring to as "The Ending" is in fact the 'Epilogue" to LOST and as such was Great gripping and emotionally satisfying TV. Especially juxtaposed with Jack's death scene. The "Ending" of LOST was Jack in the cave and everything that lead up to it, excluding the FS plot-line (which was in reality a part of the epilogue)
As such, they left A LOT of story-lines and plot points hanging in the breeze. Now I agree with the majority here that leaving SOME of that to our imaginations is good, but the volume of unanswered questions and contradictory or ambiguous story-lines does not speak well of the show we were told we were going to get. They promised ANSWERS, whether we would like them or not is not the issue. They should have stuck their chins out and made a stand, stood by their version of the story. Instead they pulled the Epilogue out of their top hat and said viola'. They thought they were pretty clever.
An example that sticks in my craw is the Eloise/Time-cop thing. The obvious explanation for her knowledge would have been Faraday's journal. It was right there in her hands in s5! Instead, they wrote Jack taking it and placing it in his pack, which ultimately gets left under a bleeding Sayid by the DI van. What the Hell???? It would have been SO easy to resolve that little plot-line and they just left it hanging instead! Its these kind of lapses that have folks a little miffed.
Of course, that's just one man's opinion and probably not a popular one. However, I figured it might be good food for thought by others. While I don't necessarily agree with the tone of "Future-Tom's" letter, I do agree with a lot of his points regarding the show. That's my story and I'm sticking to it!! LOL