Simplest interface, fastest browsing experience, draggable tabs, one-click-download manager, maximum web space (almost full screen), strong security.. you can see everything in chrome working smoothly and doesn't consume much resources. Try starting up Chrome and Firefox and see which one starts up faster :) Even the latest IE starts up slower than Chrome on my PC.
Although in terms of add-ons and functionality, Firefox might take the throne (for now), but since this website favors 'simpler' stuff, therefore this time I'll give this honor to...
Chrome - The Simplest and Fastest Web Browser
Watch this funny Google Chrome speed test in comparison with potatoes, sound and lightning =) Don't take it too seriously though.