I know it's been a while since this was posted but I'm currently working on my SOP for theory, and I'd be willing to share it as soon as I'm done with a rough draft. Although I believe it's important to indicate what area of theory you are interested in, for me Marxian theory/Frankfurt School, I think it's important to put that interest in context of research interests. I doubt that it's necessary to provide a detailed outline of your dissertation, but I think it's a good idea to make the connection between your area of theoretical interest and the research topics you want to focus on. For example, I am explaining how I intend to study contemporary social movements, Occupy etc., from the perspective of critical theory.
