thing 5 - Facebook is a good way for me to keep in touch with family and friends. I was surprised on my birthday when several "friends" sent me birthday wishes. I think the best thing I can do for my second grade students is to teach them how to be safe on sites like Facebook. Then when they are old enough, they have some knowledge of the appropriate postings for their pages.
I am not sold on Twitter. I do not have an ego large enough to believe that other people really care what I am doing as I go about my day.I don't have my phone with me at all times, so I don't think it would ever work for me.
Back channeling seems like passing notes in class electronically. I think it is more important to listen, then question.