My blog is mostly technical and the only place I'm even linked to the company I work for is LinkedIn.
I don't HIDE that fact that the two "personas" are connected but I try to keep a separation in place. My family and most of my friends don't care about the technical stuff and most of the people in the various OSS communities could give two shits about my kids pooping in the potty.
Shit, I've even got two about.me profiles.