Recently Romance University had a great post:
It is really worth a read.
I use Twitter for news, and avoid Facebook most of the time, but it seems the entire book community has shifted to those sites and almost totally abandoned decent discussion. (Plus, Twitter is all about the cliques.) Worse, social media sites now (including others like Instagram) don’t run in chronological order, so you might not see something until days after it has been posted.
The almost total collapse of book message boards – and message boards in general – means that blogs are about the only place left for readers and authors – and yet so many people seem to be abandoning those, too.
I really, really, highly recommend giving the article a read.