I have an account and use it to keep in touch with some friends who are literally all over the world. Local people I can call in the same time zone or go visit? - seldom. In fact, I had 7 friends for however long I've been using it and I checked in once a month or so.
Recently, however, a board I've been part of for about 7 years announced they'll be shutting down, so we decided to use FaceBook to keep in touch and created a group. It's been strange having to get accustomed to using real names. Imagine that - actual names.
To me, that's where FaceBook has been a good thing. It's made it easier for us to all keep in touch. It's easier through Facebook to have relationships that go beyond the activity of a forum. Many of the members call each other, and a large number of them who live fairly close to each other meet up for concerts or weekends.