That only addresses the language component though, right? You'd still be stuck with HTML and CSS. I'm okay with javascript although I'd love to see another language supported in a similar first class fashion. It's HTML and particularly CSS that feel too overloaded, document-centric, and just plain hacky. I think something a little closer to XAML, or possibly like AML, would be a great addition. It'd be great to have support for a responsive layout without having to deal with responsive design as it exists today (amazing as it is).