I haven't read the entire thing or watched the videos, but from the looks of it, it seems like a tool to build desktop apps using web technology without the DOM and CSS (e.g. the worst parts of the web).
If that's the case, it could open the door to customizable tools. I'm going to go ahead and say that I would love to see the construct 2 IDE built on top of something like that. Imagine building editor plugins in javascript instead of C++? For light tools (that means everything but image/3D/video editing and data analysis), this looks like the way of the future.
We'd get mac/linux versions automatically, Ashley would only need to maintain one language (unless the exporter is kept in c++) and performance wouldn't ever be an issue because who the hell needs beefy computers to run construct 2?
The only thing I'd miss is to be able to use prebuilt UI components like jQueryUI.