This is a very interesting post. Thanks Louis. I agree blogs still provide a better "ownership" of the content. I'm not talking (just) about legal issues and copyright, but also the fact that on blog, the writer defines the rules: the lenght of posts, the links, the images, ... the general look and feel. A blog is your house.
One things that blogs do poorly which platforms like G+, Facebook or Twitter do well is distribution. There's no "following", "reshare", "+1" by default on blogs and yet, these are the mechanisms which will send your content to people interesting in reading it.
I wish we wouldn't be stuck in a world where you have to either own or distribute your content, but right now, that's what it feels.