The first posts of the Becker-Posner blog are up. Both discuss the possible justifications of a preventative war. Interestingly, Judge Posner sounds like an economist, and Becker, the economist, sounds like a lawyer. Even though the topic of just wars is a highly politically-charged these days, both remain politically neutral (Posner has to since he’s a judge). Neither cover anything ground-breaking, but it is a good read regardless.
They also have a quick bio post.