Facebook has it's place. I'm on it for a few minutes 4 or 5 times a week. It has enabled me to connect with a few people from here on the site, and some old friends from the past that I haven't thought about in decades. I still haven't SEEN them in person, but it's good to know they are still alive and well. Even if some of them look half dead

It also lets me keep up with my sister, nieces, and nephews who I otherwise would know nothing about. Some of it is mindless banter, but some of it is nice to know, particualarly some of the photos people post. Since I don't really like talking on the phone much, it's a short and sweet way to keep in touch.
Time has NOT been kind of some of my old girlfriends I've found, or who have found me...but, they may be saying the same thing about me.
Just don't put anything on there that you don't want people seeing/reading. The same holds true for e-mail, especially at work...some people have learned the hard way that e-mail is NOT private within certain environments. Google tracks every single search you do, according to IP address. If you use the internet, your actions are being tracked in a database, even if nobody is using the information...presently.
Several people from here on the site are my "friends" on Facebook, and some of their posts are quite entertaining (in a good way).
Some people are totally addicted to it though and will post useless stuff, or things that would be better left unsaid.