is john dead or not?

Last night's episode revealed a lot of info on john locke. In the last few episodes we have thought he was dead because he was said that it was his mission to get the others to come back to the island and the only way he could do that is by dying. ben has been carting his coffin with his "dead" body in it all of los angeles. i have always been skeptical of john's death because he is such a huge part of the show and is supposed to be the leader of the island. i'm really confused on why ben freaked out and killed john when john said that he was supposed to go find elowese. i think that ben got jealous of john because she has always ben the person that ben has to answer to, and now john has taken his place. i tried not to trust charles whitmore too much in this episode and admit i was even feeling a bit sorry for ben, but after i saw what he did to john i found myself siding with whitmore. when i saw that guy in the beginning of the episode that ended up schoffering locke around, i knew something bad would come of it. that guy creeps me out because he is always showing up randomly throughout the show, like when he showed up at the mental institution with hurley a while ago and scared him away talking about some mysterious job working with oceania airlines. i was super suprised when he got shot because he had a pretty important role in the show, working for whitmore. back with more theories soon..