I found the ending far less satisfying that previous finales. Usually there is something to give you hints of what you might expect next season. Season one's Walt getting kidnapped and staring down into the open hatch. Season two's revealing the Others and the capturing of the main characters. Season three's "We have to go back, Kate." Season four's Ben and Jack conversation and Locke in the casket reveal. They all gave us a fairly good idea of what might come next season.

This ending wasn't bad, but it is the first time a season of Lost ended and left me clueless of what to anticipate next season.

I thing we are safe to assume that Jack did this exact same thing before, and is in fact the cause of the incident. After the whole 'trying to kill Ben is essentially what turned him into a monster' plot, I think a lot of us assumed Jack trying to stop the incident is what caused it to happen. But then Miles comes along and spells it out to us, setting it nice and cleanly on the table, which now has me thinking things might change, and that Miles line was thrown in there to knock us off stride.