Lindelof says the castaway connectivity we've seen in recent episodes (Hurley in Jin's flashback; Sawyer in Boone's flashback) will continue as the season chugs toward its finale. Moreover, Locke's recent comment about his "not cool" father will be mined in a future flashback (this season? next season? who knows?) and Sawyer's appearance in Boone's backstory will be addressed this season.
Lindelof offers a couple more notable tidbits: