It's curious to see that many pet projects are going public at the same time, all having the same goal of bringing control over the contenteditable madness through a custom data model.
We at CKEditor are going in that exact same direction [1]. We are making a strong switch to the project, wishing to make it a powerful editing framework, just like Draft.js but in a larger scale.
[1]: https://medium.com/content-uneditable/ckeditor-5-the-future-...