I've been wishing for something like this for a long time, and expect it to be hugely valuable.

Feature requests:
Ability to swap versions rather than merge or create a new one. For example, we might want one version of a page when an item is in stock and a different one when it is out of stock. (Without testing, I'm thinking maybe you can do this in effect by creating two clones, editing and merging one while keeping the other to reverse the change later?)
Ability to have merge (or swap) occur at a specified time. For example, new version takes over after the April 15 tax deadline passes.

Meanwhile, I'd like to know what it takes to have all those settings boxes available for constructing a page. Is that all custom, or is there a plugin that makes it easy? Talking about where the video shows "Call to Action," "Page Settings - Featured Posts," "Content Sections."