Call me cynical, but I just don't see Facebook adopting a sane moderation system, like for example anything that approximates slashcode. Their equivalent of "moderation" would better resemble censorship. They would simply hide the thoughts and comments they don't think you would like. Of course, it would be for your own good...
It's likely that a portion of the story is something that we also see here on /.: None of them really support anything that might be called a true "discussion". The reason both here and FB and the other "social media" is the approach of having a running string of "latest" topics, which quickly scroll off the bottom and out of sight. If you don't happen to see a thread in the first hour or so, you generally won't ever see it, and won't contribute to it. So, except for a few rabid topics like religion or partisan politics, where a small group can have fun running it out to thousands of rephrasings of each person's personal views, most discussion threads are typically shallow, and peter out at a depth in the single digits.
I've talked to a number of people here who express disappointment at how shallow the /. discussions usually are. They start of hoping to find in-depth analyses that point them to information that they hadn't run across or noticed. But they're disappointed with most of the threads, which only repeat a few things that those familiar with the topic already know, and then the threads just stop.
FB is quite a lot worse this way than /., of course. I've been on it for some years, and I've never noticed a "discussion" that got to depth greater than 3. I'm sure they exist; I've just never seen them. And a lot of my friends are quite well-informed "geeks" who in person can engage in long discussions. Why don't they do this on FB? Well, they may try, but quickly learn that few people ever read, much less reply to, their comments. Over here, we do sometimes get a bit deeper than that, and I've seen a lot of good information here at depth 5 or 6. But still, that's not very deep as discussions go.
I've seen much better (i.e., deeper and more informative) discussions on nearly every mailing list I've been on. If you want actual informative, socially interactive discussions, that's a noticeably better model for a forum's structure.
But the "social media" is primarily just an electronic form of the old "see and be seen" sort of social event. Such things have always been known as shallow and uninformative, although they can be fun if populated by the right crowd.