That's the reason I de-activated my Facebook account after less than one month. I didn't like the stuff people I'd "friended" were putting on my "wall."
The lesson I took from facebook was this: in most cases, you don't want to know about the people you've fallen out of touch with. Not all, but most.
I actually enjoy “unfriending” people. Is that sick or what, lol?! It’s almost like magic! I only use facebook for my interests in theatre and film and have met some pretty smart people - almost all apolitical. But I truly have to rethink this social network stuff. Some real sickies out there.