Kim,
Yes, communicate what is expected, get involved and vary your communication. This past semester I did a discussion board with my students in my online class in Twitter, Facebook and Blackboard. I wanted to "go to where the student are" - Facebook, etc. Facebook was effective, there was minimal involvement in Twitter and Blackboard had the most involvement with students. Now I know "where they are" - at least in my class.
It's important to figure out the best ways to communicate with your students.
