It seems like all the Web 2.0 things break down to public-- like Reddit, say-- or "self-owned" like a blog or FB page or email. That is, it's MINE and I'm communicating with the world, but in a public setting, it's a public forum and I participate but don't "own" it.
Twitter is "public," while Facebook is "owned." Youtube is public, but Pinterest is "owned." Hmm. Does that make a difference when we choose media for classroom learning?
And my FB page isn't "private," rather it's "private property." I'm still interacting outside myself, but I'm in control.