When I was actively teaching, I was much more concerned about not only how I acted, but also how my friends behaved around me and online. As my networks grow, it has gotten to the point where I can't be everyone's mother.
If you have other peoples' data (status updates, images, audio, video) aggregating on your Twitter pages, Facebook profiles, blog comments, and so on...
How much control do you exert over their online behavior?
If someone you follow curses, or is just disgusting, is that an immediate "stop following", or do you send them a private message asking them to clean up their act? I've come to realize that this situation is similar to hearing profanity at the mall, your children seeing an angry driver flipping someone off, etc. If you have no control over that, is online any different?