If you want to understand the brouhaha over the White House press corps whining about its own marginalization at the hands of the Obama administration, what you really need to do is read Kelly Clarkson's blog post responding to something veteran record producer Clive Davis said about her in his new memoir.
She wrote it, presumably tweeted about it, and then through some chain Amanda Terkel came to tweet it and that's where I saw it. Clarkson is famous, and we're at a point in technology where if you're famous you can communicate to people. It wasn't like that in 1992. Back in 1992, even a very famous and powerful person had to communicate to a mass public through a handful of national TV broadcast networks, one cable news network, and a few major magazines. There were a lot of newspapers, but each newspaper generally only covered one area and faced little competition. If the Dallas Morning News chose not to cover what you were pitching, Dallas newspaper readers wouldn't read about it.
And few people are more famous than the president of the United States, or have more dedicated staff on hand to help him communicate through other channels. One can rage against this trend or not as one likes, but it's pretty fundamental. The smaller the number of distribution channels, the more powerful people had to bow to the whims of the powerful people who owned the distribution channels. Today, controlling a distribution channel doesn't make you as powerful as it used to. That's good for Kelly Clarkson and Barack Obama, but bad for the White House Correspondents Association.