Google appends a ?_escaped_fragment_= onto the url and the spiderable package serves up a copy of the article from phantomjs. See http://differential.io/blog/thank-you-dhh-and-others?_escape...

Fair enough, but why not render the content along with the page for the first time instead of showing nothing for a few seconds?

How does it work with search engines? Do you regenerate a static html version every x seconds?