The Gutenberg Editor was released recently as a plugin for beta testing. Please note THIS IS A BETA PLUGIN AND SHOULD NOT BE USED IN PRODUCTION. If you’re not familiar with the Gutenberg Editor, it’s a reimagining of the post and page editor in WordPress slated for release with version 5.
“The editor will endeavour to create a new page and post building experience that makes writing rich posts effortless, and has “blocks’ to make it easy what today might take shortcodes, custom HTML, or “mystery meat’ embed discovery. ” –Matt Mullenweg
It’s been the focus of the vast majority of the work towards WordPress core this year. Given their goals and how it appears to be working so far (they are making a TON of progress), this could drastically change how we build out sites, and how users interact with their content.