Facebook is highly pervasive and because it allows users to make singular spurts of writing, there is very little need to develop the entire thought process into something credible or useful. This is not good if we intend to develop a thinking masses.
The ability to make a proposition and thereafter craft a sustained argument for or against the proposition is an important skill that people ought to develop. Social media like FB (and Twitter and any other simiar kinds) where a singular sentence or utterance is sufficient to pose as a response or entry is particularly disheartening.
Initially, the novelty of it all makes it chic to be a user of FB. Thereafter, one ends up being hooked to FB because it is there. There is almost no such thing as a writer's block on FB because one needs not always begin a conversation. One can easily make a comment on an existing conversation and be noted. In this regard, the attention given to the utterance is in fact a kind of reward to encourage repeated visits to make more of such entries.
By and large, one starts to prefer FB over other forms of social media requiring more writing and less instant gratification (of being noticed). Very soon, we will see arguments made that are of deteriorating quality. This is alarming but until the trend can be reversed or people can overcome their tendency to choose the lazy way out, society risk become stupider and less able to sustain an argument.