Since JSON shows a lot of benefits over HTML, why don't just abandon HTML? Qt frameworks with QML shows it is perfectly possible to use JSON to design rich content
Many of you think about this question in terms of performance vs html but i'm not about that.
HTML is just less readable and it's not enough per-se to describe UI behavior, look and feel. Maybe a technology shift is needed. I think from the developer point of view.
What about a browser capable of rendering a QML like web-page for example? QT with QML uses google V8 engine to do its work.
If you can write a web page in a technology that is not HTML, people will start using it. Browser could support HTML for a long time and allow developers to code with less stress