[tracker1]

I tend to use CSS for the bulk of layout. Lately leaning on say Twitter Bootstrap as a base... and using JS for some tweening, or other points. I also use Modernizr, and other JS to enhance classes in the HTML element for CSS use. I find this works pretty well... I can keep my rules in CSS, but can enhance them via JS. My enhancers are the only script I put into the HEAD (before the CSS), all other scripts are just before the closing BODY element with ads and analytics last of the scripts. I do think that having a good base CSS knowledge is important.

The exception to this, would be a full-screen site/application where you are using the full field of view for an interactive display, or simulation. Then JS leaning and even canvas are more important for interaction.