Social media allows you to do just that, be social. Sometimes it's hard to talk to people in person, but with the technology we have today it allows you to talk to anyone in the world without the anxiety of actually talking to them face to face. It also allows you to say what's on your mind more because it's easier to say what your feeling by pressing buttons on a screen than it is to actually have words come out of your mouth.
The reason I believe this is because you can converse back and forth with the new media that is out there, unlike traditional writing on paper or on an internet page. Having people interact with you creates bonds that weren't available before and in my opinion that makes it much more intimate.
10 years ago when people saw something online, they would usually read the whole article or most of it to get the important points out of it. Now, we see things go viral and we see their headlines and maybe a point of two about what the article is about and we automatically assume its all true since we see it numerous times a day. The ability to go viral has allowed false information to spread like wildfire.
For example, if you use incorrect grammar on a Facebook post, you're likely to get called out by the "grammar police" of the Facebook world. However it is allowed, if not encouraged on twitter, to make grammatical errors because they only allow you 140 characters which isn't enough to have a perfectly spelled tweet if you have a lot to say. So depending on what you platform you use, you will see the different politics between the sites.
I can see this argument going both ways. It's helpful because students can converse with one another at any time and place because you don't have to be in a classroom to use twitter. So this can expand the opportunity for learning beyond the classroom. However it can definitely be a distraction because it is very easy to get caught up in your feed and not pay attention to the discussion going on.