What I like about Facebook is that you can keep it tightly locked down - I can choose exactly who I want in my network, unlike the other channels I loiter in, such as Twitter* and this blog, where it's impossible to block people you don't like.**
This is a good thing, because the value of any online community depends on the quality of people who participate it, so by making sure that only people I like can connect with me on Facebook, it's become a happy little place full of good humoured banter and interesting conversations with a broad spectrum of people from different parts of my life.
To keep it that way, I'm pretty strict about who I connect with. Friend requests from random people who only vaguely know me, people from school, friends of friends who I don't really know, and almost all colleagues are usually rejected. My general rule of thumb for accepting Facebook Friend requests is: Would I be happy to go to the pub with this person for an evening?
Sometimes quality control slips a bit. I recently got a request from an old colleague, and despite not being in contact for over a decade I accepted because we always used to have a giggle (and I kind of fancied her back then). This was one of the first things she posted after we connected:
Unfriended her pretty much instantly after reading that shit.
*Twitter has a feature to block specific users but, ironically, anybody who is not actually logged into the site can see your profile page, unless you completely lock down your account so that only users you've individually authorised can see it - but that kind of defeats the object of being on Twitter in the first place.
**You know who you are. *flicks vees*