That link describes a method for translating a URL where a static version of a dynamic page can be found. So you still have to serve and generate static content yourself. So we're not quite there yet. But seems like at least Google has started executing _some_ JS. There are more search engines than Google though :)

Time till the page is usable comes under consideration. You can load the relevant html then begin the bootstrapping of the app.

If I recall correctly, Twitter had this problem. The size of their apps + templates bloated to 2MB or so - making that initial page load pretty bad.