Lost's Final Five (Or Six?)

In less than two weeks, Lost is back with the remainder of Season 4. Whether that means five episodes or six is yet to be determined. Here's a look at what we do know (thanks to EW's Jeff Jensen, and various posts on DarkUFO and LostPedia). First, some overall observations, and then an episode-by-episode preview.

Overall, we'll learn the following:

How the Oceanic 6 leave the Island (not rescued by the Freighter?)
What happens to the survivors who stay behind on the Island
Why Sayid is working for Ben
Who's in the coffin
A new "game changer" at the end of the season (like last year's flash-forward)
We'll see "all three levels" of The Orchid Station
A "major and mysterious" storyline for Claire (finally, my girl gets some much-needed attention!)
Penelope Widmore, Charles Widmore, Richard Alpert, and Matthew Abaddon will appear

Episode 9 - The Shape of Things to Come (April 24th)
The flash-forward is focused on.....Ben........(highlight to reveal).
The Barracks are under attack.
The Smoke Monster will appear, and its mythology will be expanded.
Here's a brand new promo from ABC:

Episode 10 - Something Nice Back Home (May 1st)
The flash-forward is focused on.....Jack........(highlight to reveal).
Walt's Island visitations are "alluded to."

Episode 11 - Cabin Fever (May 8th)
The flashback is focuses on.....Locke......(highlight to reveal).
Richard Alpert will appear.

Episode 12 - There's No Place Like Home (May 15th)
No details yet.

Episode 13 - Untitled Season Finale (Unless a sixth hour is greenlit by ABC)