These are relatively new terms for me, I'll admit, which means I'm only slowly getting a sense of what they suggest conceptually.
Here is a fairly strong statement of the writable future of publishing, by Terry Jones: http://radar.oreilly.com/2010/12/the-future-of-publishing-is-wr-1.html.
And a little excerpt, in case you're glued to this screen, as is only fitting:
"Publication of information obviously includes traditional media, such as books, newspapers, magazines, music, and video. But we can generalize considerably to include blogs, tagging (e.g., Delicious, Flickr), commenting systems, Twitter, Facebook, and Myspace.