From an interesting Jay Newton-Small piece on Sarah Palin:
Her first Facebook post, in August 2009, accused the Obama White House of creating "death panels" as part of health care reform. That offhand remark, as inaccurate as it was incendiary, helped incite weeks of embarrassing town-hall meetings for Democrats, which in turn nearly brought down the Administration's top priority. Palin, working at the time in San Diego on her first book, was surprised by her post's galvanizing power. With just a few keystrokes, she discovered, she could ruin White House press secretary Robert Gibbs' day, or as she puts it, "I find it a great way to communicate with people directly without the media filter."
Of course Facebook is media. Palin means a traditional nightly news or print journal media filter, and while Facebook is certainly different than those (i.e. she's the editor not some other entity), the reality is is that Facebook is a media filter.
And as McLuhan told, the medium is the message. [Edit: My use of McLuhan here has been criticized. See the comments for that discussion.] A question worth asking is what the message of Facebook is? The mediation of a tool whereby you simply declare the truth (what Colbert calls truthiness, of which Palin is the Queen).
This is what I was trying to get at in my piece reviewing Palin's media strategy with French post-structuralist philosopher Jean Baudrillard. One of Baudrillard's descendants Thomas de Zengotita covers this topic in his brilliant text Mediated: How The Media Shapes Your World and the Way You Live in It.
As Baudrillard said, by the repetition of a narrative, of employing rhetoric, we end in a simulacrum, in a hyper-reality where nothing is quite real and everything comes through mediated filters.