A detailed/dynamic syllabus is key to an online community. It must be detailed and yet able to change as issues or improvements arise. Remember, a flat text does not build this, it must be a "live" format (i.e, audio, or video, links, and detailed explanations). As S2I communication, is important to help a student feel apart of the community, so is S2S. You want to think of various ways to meet everyone's learning styles and comfort levels.