[DerfNet]

>1) I'm in a couple specific regional groups that AFAIK have no non-Facebook counterpart (though they easily could). I think Facebook does groups poorly, but they serve the "non-technical community space" use case much better than any other popular offering that I know of.

These used to be called "forums" and were very popular until Facebook invented groups and murdered them all.

[colanderman]

Forums traditionally have been difficult for non-technical users to set up (requiring at a minimum configuing and paying for a shared web host). Certainly I don't recall any popular "managed forum" service pre-Facebook.