After watching "What Kate Does", I think the general consensus has been that MIB is probably responsible for the "claiming" of Sayid, Claire, etc. Sayid's torture brought back memories of Season 2 when Walt said that the Others were conducting "tests" on him. Could it be that these tests were to discover if he was infected by the darkness too? It hasn't become fully clear whether one has to be dead to be claimed, but since Sayid was, and since Claire was speculated to be after the explosion in "The Shape of Things to Come", perhaps Walt died in his early days and was possessed by MIB? Admittedly, this is unlikely, since Walt was allowed to go home, thus his abilities are not likely to be the result of any possession! Still, it would be rewarding if we found out that Walt's capture was related to MIB. Share your thoughts.