Social networks can have their merits… you will just not find them on Facebook.
I like the small-scale initiatives where you just hang out with (remote) friends and have no incentive to make yourself seem different than you are. Like the example of Scuttlebutt presented in the video here.
Many people will find lotsa things missing when looking at the bare UI and comparing that to FB. But they have to ask themselves what are the true reasons to use a social network (or at all) - as you rightfully ask also @healthyswimmer - and then take it from there.