[npsimons]

To me, this seems to ring true - growing up I knew our neighbours (and so did my parents), but now I can't name any of my neighbours. The problem seems to me to be one of a disconnect, or different priorities: I have hobbies, things I love to do, and as far as I know (because I don't know my neighbours), my neighbours don't share in those interests. Given a choice between spending time with people I have nothing in common with (besides geographical location) and pursuing my preferred activities, I choose the latter. This is also why I don't know many of my co-workers very well.