what do you usually do when you're inbox gets spammed with a lot of irrelevant information - you apply filters / labels. same thing can be done with Facebook, but for some reason people still treat it as a service that doesn't need any customization. you just login and out of the sudden quality information starts pouring down from all panels. it's not like that... it's just like with your inbox, even though your friends aren't really selling Viagra, but some of them aren't far either.
every post on your news feed has got a tiny "hide" link, which you can use to either unsubscribe completely from a friend's wall posts (yeah, keep those "how I met your mother" quotes for yourself bro), choose which kind of news you're actually interested in (pictures only, events etc.) or even choose how often you wanna see a person's posts ("all updates" or "most important"). if you get the tendency to disable a post that you don't like the moment you see it, then (on the long run) you'll end up with a wall that's at least 2/3 interesting or let's call it decent (facebook is not really hacker news). I'm not aware if this is the actual implementation, but would be really cool if Facebook would actually learn from the posts you hide and stop suggesting similar ones in the future.
I've got around 300 friends and had I not unsubscribed from a lot of them, my news feed would have been packed with wedding pictures of people I don't know, events I can't go to or causes I don't really care about.
just to end here, email has its purpose but that purpose is not social sharing any more. just like emails took over writting letters years ago, social networks should improve over emails in the aspect of sharing information with ease.
oh, and to the author: the facebook experiment hasn't failed - you just need to tell it what you expect of it.