I was watching "Greatest Hits" the other day randomly and had a little bit of a stroke of genius . . . maybe.
During the scene where Charlie resuces Nadia from the burglar I was thinking about how Jacob came into contact with different characters at different times (im under the impression that he intervenes their lives and points them towards getting to the island) and thought that the burglar might well be Jacob. It was pouring down so you couldnt really see his face well which would cover the whole not having an actor to play him at that time thing so i guess it could be. This could also mean that at previous points in episodes Jacob could of been seen again. A bit of a long shot as they didnt have that guy from Dexter in it at the time but i think it would be a neat twist for some Jacob related flashbacks in the next series.