Facebook is ... what each individual makes it out to be. Private or public, updated status changes several times a day, or none at all. It's what YOU the member decides.
I use Facebook.
Sure ... I'm addicted to Znyga poker. Now I could play on Yahoo, but then I might miss out on something happening in a friends life. This coming November is my 25th High School Reunion. To date, I have not been to a single one. Up until about a year ago, I was in contact with only one friend from HS. I went out of my way to stay hidden and private. ( kinda like my FB is ) Over time I reconnected with friends. Today I made the executive decision to attend the reunion in the fall. (dependent of whether my mother can stay with my kids for the night) I'm excited about seeing friends who I haven't seen in person in so very long. And you know what? It's all because of FB.
Now, about the folks who air their dirty laundry on FB and those folks who think we give a rat's ass that at this moment in the day they're doing this or that. Pft. Who cares????? Much of it is the need and desire for attention and to feel wanted or to fit in. The more responses one gets from their status change, the better they feel. Right?
I will say, I have a large group of political (friends and acquaintences) who keep me in the loop with the latest stories in the news. There's always something to read when I log on. ( and chips to be won! )