My mother, who works in the socal services, deleted her facebook account after two days. She didn't want her clients as friends, and she didn't want to ignore their requests. My mother is probably too good in her job, has too much conscience and her clients feel too personally connected to her.
I agree with her. She shouldn't have to deal with her clients in her spare time, and this is one of many valid reasons for not having a facebook account.
I have one, but I hardly ever post anything there.