Here's an interesting article by Jonah Lehrer - Author of Proust was a Neuroscientist.
“And this is why we should all follow strangers on Twitter. We naturally lead manicured lives, so that our favorite blogs and writers and friends all look and think and sound a lot like us.”
Read the whole article - it's really fascinating. In a way I think art can act as the "stranger" on twitter - introducing ideas/images/emotions into our otherwise predicable days and as he says, "expand our creative potential."