I know many were expecting answers to their questions to come out quickly in the final season, but for what it's worth, this season seems no different than any other. There are new questions, few answers, and a completely different direction. The writers have an endgame, and with limited time, they are still taking things slowly. I completely trust Damon Lindelof and Carlton Cuse to deliver in the end, though many capable showrunners have bungled the final season in the past. Fans who've hung on for five seasons only have one reasonable choice--hang on for one more season. Whether they like it or not, there's no turning back now.
Sayid, having just come back from the dead, seems perfectly normal, but the Others want to preform a test on him. In his backward way of doing things (reviving by drowning), the Japanese guy who we later learn is named Dogen, shocks Sayid and then touches him with a red hot poker. Like any human, he screams in pain, but the Others in their supernatural way, tell that something is wrong with him. Dogen has a pill for Jack to administer to Sayid. Naturally, Jack is suspicious and doesn't give it to Sayid, choosing to swallow it in front of Dogen. Dogen pummels Jack until he spits in out, and then reveals the truth. There's poison inside the pill. Dogen explains that Sayid has been "claimed," and the same thing happened to Jack sister. Is it the same thing as being "infected" as Dogen said earlier?
Fake Locke wasn't in the episode, so we didn't get any extra clues from him. The Others admitted that the temple was to protect them from Smoky, and Dogen explained that if the darkness reached Sayid's heart, he would become a completely different person. Claire's appearance at the end with the wild Rousseau-esque look on her face was the big twist of the episode, but it could mean anything. She disappeared into the jungle randomly after seeing Christian who I assume is MiB or Jacob. (The distinction between the two is hard to discern considering how intertwined everything is.) Somehow, Claire and Sayid (who I assume was revived by MiB or Jacob) came in direct contact with these powerful beings, and contracted the "sickness" everyone has been talking about for so long. The French got changed after being dragged into the temple by the Smoke Monster and coming out after a long time, so the same thing probably happened to Claire who was missing for a while. She does react to Jin instead of simply shooting him, so there could still be something left in her.
Between all the events that force mass speculation was a sad story of a man who had just lost it all. Sawyer breaks out of the temple (and I suspect the rest of the islanders will follow suit soon), but the Others need him back, so they send Kate, Jin, and two Others to track him. Kate, in her quick-thinking, impulsive manner, takes out the Others using a trap that wasn't set by Rousseau (a trap for Smokey?). She finds Sawyer in the barracks and he is a total mess. After thirty years, his box is still under the floorboards, and out on the docks, he shows Kate the ring he wanted to give Juliet. This part of the episode helped the episode greatly when nothing else made sense. Going back to Sawyer and Juliet kept the episode somewhat grounded, and prevented the episode from being a jumble of events that will have an explanation later on. We know in the present that Sawyer is suffering and there is nothing Kate or anyone else can do.
At the same time, Kate is despairing over how terrible things have become. She came back to the island with Jack in the hopes that she would save everyone. She was perfectly happy with Aaron, but came back only to make matters worse. She caused Sawyer an uncountable amount of grief, and everyone else is at the temple with no clue what to do. Luckily for her, Claire is finally back, which means her quest to reunited Aaron and his mother can proceed.
And there's still the events going on in the alternate world/whatever you want to call it. From the interviews I've read, the island and Los Angeles are not in completely different universes. They're tied together by more than mere foresight of Faraday's theory. I don't know how that'll work, but we got a better peak into what's going on, and there were some tie-ins. Kate's hijacking of Claire's taxi works on due to the police not doing anything. The taxi is stopped several times, and the driver even bails, but the police never arrive. Claire also gets out, leaving Kate to ditch the handcuffs. Kate pulls stuff out of Claire's bag including the same killer whale Aaron had, and she realizes that Claire is a pregnant woman that was just treated like trash. Kate heads back and picks up Claire who accepts Kate for a good person. The woman who was supposed to adopt Claire's baby is no longer interested after her husband leaves her. Claire has no more options, but the woman couldn't care less. Claire starts having pains, and Kate takes her to the hospital where none other than Ethan works. This will be interesting.
My big theory from last week that Jacob reanimated Sayid is dispelled if Sayid truly is infected. That Last Supper poster could have been a red herring for all we know. An infected Sayid as Judas certainly carries less weight than a Sayid that is actually Jacob. Could MiB have infected Sayid only to have Sayid turn on him later? MiB may expect infected/crazy Sayid to completely be on his side, but the human part of Sayid could win through and betray him. The series finale is Sunday, May 23, so the answers will come soon enough.