I tend to keep my microphone off. I don't have the best privacy in my house, and sound travels. So it is easier to leave it off. Once in a while, when I am absolutely alone in the house, I turn the mic on for private shows.
The thing about non-audio shows is you've got to be engaging - I would say even more so than usual. Chat with people, tell jokes, make faces, dance to the music the people in your room can't hear.
I do well with audio off because my typical MFC user is viewing me in secret - at work, next to the sleeping wife, in the carpool. There are definitely users looking for models without audio.
