I just want to note that the lack of plot development is not an issue in this instance - in fact it was quite welcoming. The pace of the season thus far has been quite fast, and the plot has had little cohesion (goes from one aspect of the storyline to another).
What the audience did see was infact a lot of character development.
We saw Dexter at his best in this episode - especially when he was mocking Speltzer (sp?). Dexter made a two sacrifices this episode, sending his son to Rita's parents and finally letting go of his blood slides (which I found him to do all too easily, considering he based his whole 'ritual' on getting a blood sample).
I get the impression that Deb is all over the place emotionally. Whether this is intentional remains to be seen, but there's a significant lack of consistency concerning her. She's also definitely feeling frustrated at how poor the judicial procedures are against criminals, which in turn makes her appreciate Dexter more - something I expect to see more of come the season end.
The brotherhood are proving to be confusing. I was beginning to see them as intimidating, but not so much now. I also don't think they want to kill Dexter - at least not yet anyway - as they would have done that as soon as they knew who owned the boat.
Overall, 'Run' was a fully entertaining episode which contained everything bar plot development. Hopefully this is more of a bridging episode in order to slowly pave way for latter half of the season (as if we're saying that already!)