This episode was good in terms of character development, but really did nothing to advance the mythos of the island. If you listened to the official Lost podcast, you'd know that they said this episode was basically about making Sawyer look like a badass again because up until this point, he had been turning into a big puss.
It was interesting, but really didn't tell us much we didn't already know. Probably the most interesting parts were (a) the fact that Charlie has gone all Anakin Skywalker, and (b) now the two big leaders on the island, Jack and Locke, don't really trust each other anymore. I think that one of two things could happen: Either everyone will band together and beat the crap out of Sawyer or (more probably, in my opinion) the entire situation will implode and there will be mass chaos. Whatever happens, I'm sure the Others will love it.