Michael is Bens man on the boat.

First theory sent in by Croucher...

When Michael made the deal with Ben to be released from the Island, he told him to head on that compass bearing and he would find help. Well I think that Ben knew where the freighter was and Michael had agreed to go and spy on the boat after learning some secrets of the Island.

Ok, so, Ben and Michael are in communication, and Walt, with his "powers" is also communicating with Locke. Michael will arrive back on the island on the freighter and redeem himself for betraying his Losties.

I think that maybe Wildmore has taken control of DHARMA, away from the Hanso foundation. Ben has the support of the Wildmores, and the Island helps with the pharmaceutical testings... The Wildmore are told by Ben that a plane has crashed on the island, and that people will come looking. Wildmore then sends Talbot on Christine 1 to go and "find" the wreckage, which has been staged by the Wildmores. This way the outside world would not come looking for the island. This supports the idea that DHARMA food drops etc are still being delivered. DHARMA might have ceased, but maybe Wildmore has taken control and using the island through Ben.

In the meantime, Hanso Foundation has got annoyed with DHARMA, and because Ben has stopped all communication to/from the Island, Hanso can’t get a team there to investigate. Therefore, when Hanso hears of a plane crash around the place the island is meant to be, he hires Michael Abbadon to group a team to go and investigate - knowing the islands electromagnetic powers could bring down a plane. The team is Naomi, and the freighter people. Abbadon (in Naomi's flashback) seems really sincere about there being no survivors, and maybe he believes that the plane is real.

Ben has been alerted of Hanso sending a team to the Island - and knows they aren't happy that he purged all DHARMA - so sends Michael with the cover story of he is a survivor that has escaped Ben. He will then feed them info (that Ben has already agreed) gaining their trust, and secretly sending info to Ben.

Ben knows that "the temple" or others places of the Island are safe to hide... and that’s why he sent the "others" to hide there.