Oh boy. Um, the short answer is No. My husband knows, obviously, and is pagan himself. So he's completely comfortable with it, and the altar in our bedroom. His family is kind of pagan/atheist. So I'm not sure if they know, exactly, but they don't really care.
Most of our friends know, and are also pagan and/or don't care.
My family, however - that's a different story. (Though I did link to this blog off my Google+ profile page, which they're on, and I'm using my real name, so...if they've stumbled across this blog they haven't said anything.) My family is very conservative Christian, with the exception of my mother's mother, who is the lone Democrat. But probably would still not approve of my beliefs.
I really don't know what would happen if they found out I was pagan; I'm sure my father's parents would be sending us letters and cards and trying to witness to us over the phone and save our souls and I don't know what else. Dad would probably just give us stony silence. I have no idea what my mother's reaction would be. But yeah. They don't know. And living on the west coast, while we live on the east coast - I don't feel the need to tell them.