Yeah I've got to agree, if I thought my kids where in any kind of danger, I would not leave them with that person.

Having worked as a babysitter yes, I would feel very violated if someone filmed me without my knowledge...say I decided to pick my nose once I'd checked on bub...how embarrassing! I'd rather just have concerns raises directly, or, if the parents were that worried, just find someone else. I know if I were at that stage where I felt I needed to film someone, I would be looking elsewhere.