[dajt]

I only use facebook for the model engineering group(s) and unless they decide discussions about miniature locos are dodgy I should be okay.

I can see there is a potential trap there for the people who decide to mix their personal and professional lives on something like facebook. I just think it is unlikely to get sprung, and comments like "why on earth don't they take complete control of their online presence and register their domain, get their system hosted, set up all their e-mail addresses, etc" could only be written somewhere like HN. The rest of the world would just shake their head slowly.

[mnx]

Yeah, I agree. But I think mixing personal and professional on Facebook is pretty much by default, and most people do it. Also, the illusion that people could control their own presence comes from the fact that this is how it used to work, back when the internet was a much different place.