A few puzzle pieces are offered up, but not many
And, no, I don't mean "lays pipe" in the sexy fun-time way. I mean it more in the "lots of exposition" way.
"Lost" has always had trouble following up their typically-impressive season openers. It's just the mechanics of storytelling on television, I think, because they have all summer to figure out exactly how they plan to punch you in the face right out of the gate, and then they have to settle into the business of actually telling the story for the season, and that requires a shifting of gears. This year is no exception, and 6.03 ends up moving a bunch of pieces around the chess board without advancing much of anything. There are a few tidbits of note, but for the most part, this is all about getting things in order for bigger episodes ahead.
It's interesting that there is so much disagreement between "Lost" fans about what is happening so far this season. I'm seeing a lot of speculation out there that the storyline that takes place back in Los Angeles is actually the future, after the storyline that takes place on the Island, and that they aren't alternate timelines at all, but the same timeline at two different points.
I vehemently disagree.
I don't believe for a second that the two timelines are going to remain separate, but I think they are running parallel at the moment. What's going to happen later this year if my guess is correct is that some event is going to have to take place that pulls the two timelines into one, merging them. Neither will be completely erased, and the events we're watching will have ramificiations in both timelines. I don't think the "Lost" producers would be cruel enough to waste giant chunks of the running time this year with something they'll wipe out later with a simple, "But that didn't REALLY happen" sort of narrative double-back. No way.