I don't think Facebook can really be judged as a website. It's not really a "part of the internet." You really can't compare any social networking service to a serious online community. When judged as an actual community, Facebook is doing pretty bad. As a social network mostly reserved for people who don't get around the internet very often, Facebook is doing fine.
Just lower your expectations of the spacebook/tweeter/instaface "websites" and you won't see so much of a problem. Any complaints should be forwarded to society as a whole.
Though it is my personal opinion that the social obligations that come with having/not having a facebook account are coming alarmingly close to some sort of diabolical Orwellian bullstuff.