In any web development company, there exists two different worlds; well there are more, but we'll just focus on - front end (designers) & back end (developers)
The Front end guys are responsible for making something that is visible to the end users (THE LOOK). The back end guys are responsible for making the front end work (THE FUNCTIONALITY). Together, they both deliver a complete web application/site.
The back end developers would typically use programming languages, such as Java/C /Python. Apart from talking to database and processing requests, they even have an arsenal of libraries to generate the site markup (JSPs, server side templates, etc).
Front end guys usually fill in by writing HTML documents and CSS files (merely a writer) to present this markup in an visually pleasing way and back end just take these templates to populate data.
Because of this cultural difference, there's always been a ego-war between these two worlds. Even the company management would rate the front end guys par below the back end developers because the front ends guys don't do any serious programming.
But, this didn't change anything on the server side; the server programs were still running on JVMs/Rubys/Pythons.
This rise of the front end developers poses a real threat to the survival of back end developers. If you are one of that back end guy, do you already realize this threat? What's your game plan to stay fit to survive this challenge?