Lost Season 5 - Spoilers EVERYWHERE! :p

[McLovin']

That's because this finale didn't answer much...We are still left at the end with "did this cause the Incident or not." and as well with who Illana's group is. This ending wasn't a gamechanger like Walt being taken, the Swan imploding, flashforwards, or the island moving. It was just a bomb going off and Jacob dieing...

If you noticed, Jacob explicitly touched each character in their flashbacks. Even for a casual viewer it was pretty apparent.

From a logical point of view (lol), Nemesis wanted to kill Jacob but couldn't do it himself so it needed someone who would do it for him. But not just anyone could waltz up to where Jacob resided and so Nemesis (who I would say is the smoke monster) used different characters to manipulate them to find the one person it needed that could do the job...John Locke. It made him look like the leader of the Others in order to finally be able to get to Jacob and use Ben to kill him.

The Jacob thing is cool and I believe he knew he would die. His behavior at the end only proved that he foresaw his death. Perhaps with his death he will pull an Obi-Wan and help our Losties somehow.

And the white flash at the end was a time flash in my opinion. The Losties fulfilled their purpose of creating the Incident and will teleport to 2007 and the story will continue about stopping Nemesis.