I hate facebook. I had it once as I am a journalist and was under pressure to make use of social media. But soon closed it down (well, you can never take it fully down, thanks FB) and realised that my four best friends don't use it either so it was a bit pointless.
My main gripes:
People say their friends have chosen. Well, up to a point. But not fully. They accept invitations largely because it's human nature to want to be asked in and generally people don't like to be awkward and refuse. But they won't have necessarily actively 'chosen' to accept broadcasting of your photos and witty apercus. You have to make an active decision to 'hide' and most don't. Most people are passive, rather than active when it comes to these things.
Facebook encourages narcissism. All people have some element of this rather negative characteristic, some hardly at all, but some to pathological levels. Facebook can take your normal 'average' person and exploit their latent narcissism. Of course, you'll think you are one of the sensible non-boastful people on facebook. But will others think that?
I've certainly posted things that on reflection I think were poncey, rude or could come across as TMI. But you can't get it back. I wouldn't have come across like this on the phone or via email.
But my main dislike is that it is a pernicious influence on proper meaningful human communication (yes, and I accept the irony of me posting on this anonymous board 
). With a face-to-face meeting, a letter, an email, or a phone call you communicate directly, get a response, tailor your response, and so on throughout the conversation. This brings people truly closer and allows you to fully explore your relationship and get something rewarding from it.
On facebook obviously you can message, but a lot of contact is through status and wall posting, where you are posting into the ether to many broadcasting, effectively and I always am left feeling that person was too rude to speak to me directly. Or a braggard, or a drama queen.
Ever laugh at those dreadful Christmas letters from twatty relatives? Well, Facebook, for me at least, is like that run amok.
There are so many other ways to communicate which are more personal but which can include photos being sent, etc. I've lived abroad from family and friends and managed fine, having a baby etc etc.
Facebook is monetising you. Don't be a sap and give away your information for free. Even if you set everything to private, it is using you for cash. It's heady pre-market valuation is based on tailored advertising and information selling.
Once it's out there, your information isn't yours. It's a bit scary. You can't ask for it back.