[GotActichwicy]

My guess is (a bit convaluted but hear me out) that Ben has somehow captured Jacob, who is a spirit leftover from that slave ship. By capturing Jacob, Ben is able to have access to his powers, thus making him leader to the rest of the others. Jacob, is a distant relative of Locke, and through his spirit powers was able to bring Locke to the island, to help release him. What really makes me think this is that A) from the silloutte it looks like locke, B) Ben did not hear what jacob said, and seemed adament to know what was said, jealous almost. C) Ben shoots Locke to take out any potential threat to his prowress as leader of the others and not lose access to whatever power he is syphoning off jacob.

ok, so it is a bit far fetched, butcmon, the whole concept is.