Here is an amazing podcast from responsivewebdesign.com, on how Google+ achieved responsive design. This site has some really cool podcasts on responsive design. Head over and enlighten yourself.

How does Google make a responsive site that performs as fast as possible across a variety of different browsers?

I loved this part about responsive design from the podcast : 

(Exactly as posted on responsivewebdesign.com)

We have what I like to call our “sixty to the five rule,” which is for all browsers, all devices, do not download more than 60k of HTML, do not download more than 60k of JavaScript on initial page load, do not download more than 60k of CSS on initial page load, make sure all the animations are sixty FPS, and make sure that your average latency is .6 seconds. This has been built into our engineering processes, and it’s really required coming up with a platform and a JavaScript framework that helps you achieve these goals that we set forth. Malte can probably talk more about the framework that we’re using and how it helps us achieve this level of performance, this “sixty to the five rule.”

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