Well, the writers had me fooled.... again. I was sure that Peter was the murderer, but he wasn't. He just wrote about it. The writers did a really good job of leading us on to believe it was Peter and then twist it around. It was a reallt good episode otherwise as well, really freaky considering what some people fantasize about and what they write about. This season the writers have done an excellent job at coming up new stories and strange and twisting stories every episode.
I would have loved to see more about the replicator, but I think it's quite obvious that they plan to have that as part of the season finale.