Agree with you re. Facebook. Some of my mates posts shares and likes that make them look like right idiots when I know they aren't IRL. There seems to be lots of mushy, sycophantic ###### being shared around, e.g., here is a post of a cute fluffy rabbit, like and share if you love your mother etc.
Fbook is now overrun by deluded individuals who consider their daily motions somehow worthy of comment. For a first time user this may be amusing, for myself today was the day to shut my account. Even observing the village idiots has had it's day. It was nice to catch up with my old school mates of '85 but unfortunately the class of 2013 are just as sad as they were then.
Twitter is even worse, just a short-hand version so even the illiterate get a go. Full of mis-information, gossip, bullying, bigotry, lies, defamation, child groomers, the odd joke and, if you're lucky, an amazing insight. I just don't have the time. Unless someone comes up with a definitive "you've been framed on the internet", I think I've done my time with social networking.
I've long worked out that my trusted networks are the only ones worth having and most of the people in mine have switched off fbook, etc. Sometimes good old fashioned funny people are far better appreciated in company than taking your jokes via text or twitter.
The other thing is that once the government gets it's act together, the internet will be useful for nothing but paying bills.
Twitter is interesting that your experience is very much dependent on who you follow. If someone gets on your ####, unfollow them. After a while you'll get a good blend of people who you like who are interesting and people you don't like but still have interesting things to say.