For me, fb is useful only to keep an eye on what is going on with my family/friends specially for things such as cute pictures of their kids, marriage/birthday events etc. My wife uses her fb time to update me on those. So personally, I hardly login to fb anymore.
This is what Facebook's utility for all of us is. Just replace cute photos of their kids with cute photos of your crush (or ex), and replace marriage events with house parties, and you've hit what the twenty-somethings on fb do daily. Anything else is to justify being there.
