So, just to get this straight with responsive web design...
With @media-query and CSS3 I will:
a) not be needing JavaScript at all in order to target screen sizes @media-query screen sizes with the modern browsers that support CSS3?
b) only require response.js JavaScript fix for IE7 and IE8? (Does this fix IE6 or is IE6 fubar when it comes to responsive web designs)
c) want to build and design the mobile version first and then work my way outward to the tablet, netbook and desktop sizes afterwards? (To follow best design practice)
d) if JavaScript is disabled in IE8 and lower, the default desktop version will be applied to the site design? (No responsive web design)

Is there anything else I should keep in mind about about old browsers? Is that correct in assuming IE6 will not work with responsive web designs at all, and that response.js fixes @media-query screen size layouts for IE7 and IE8?

Also, is it only with Microsoft's older browsers that they have a problem keeping up with @media-query or are there old Safari / Firefox / Chrome / Opera version that do not support it either? I think that's all of the browsers that I will need to worry about. Perhaps I should be taking a much closer look at the mobile browsers too... Since after all, that's kind of the reason for responsive web designs in the first place! Any known phones / OS versions that have a hard time with it?