Operation Sleeper features Jack & Juliet, and more specifically the conversation where Juliet informs Jack that she is still working with/for Ben. In terms of an episodic timeline, this would have occurred between D.O.C and The Brig, and it is interesting to see how Juliet breaks the news to Jack. We get to see Juliet question whether or not Locke actually blew up the submarine and basically reinforce the amount of time she has been on the Island:
Jack – So you’re only here because he sent you here?
Juliet – Yeah.
Jack – Why are you telling me this now?
Juliet – Last night with Sun, we saw the baby growing inside her. If she’s still on this island in about a month, both of them will be dead. I’ve been living Benjamin Linus’s dream for three years. Three years. It’s time to wake up.
Interesting that this is now the 3rd Missing Pieces (out of 5) to feature Jack in some form or fashion. I am not sure that really has any implication on what we will see in Season 4, but as fan of his character, I hope so. However, with roughly 7 of these left, I do hope we will get to see more on Locke, Sawyer, Kate, et al.
As many of you know, Season 4 Trailers are now starting to show up in in cinemas, and I confirmed that with some friends who saw one prior to a showing of Beowulf this past weekend (though they said the digital 3D trailers were all a bit distorted). I have not been able to find anything online yet that looks 100% legit, but here is something I found which looks comparable to what they saw: