My wife cut off FB 2 years ago but I still use it mostly like a forum. Locally we have a group of 50ish gamers (Warhammer, 40k, Warmachine, etc) and this is the primary way games / tournaments / campaigns are set up. Even a trading area since gamer nerds are apt to constantly buy and trade their toys.

What's funny is we've had to convince our younger members to even sign up so we could communicate with them. Anyone younger than 20 in our group didn't usually have an FB account.

We've tried running traditional forums for the local group but it has never worked. FB is the only way to do it for now.