CSS3 Selectors Test
Firefox 5, IE9, Opera 11.50, and Safari all score a perfect 574 in the CSS3 Selectors Test. Chrome only earns a score of 558.
Chrome, Opera, and Safari all receive perfect scores of 100 in Acid3, while Firefox 5 earns a score of 97 and IE9 gets a 95.
Chrome has the best support for the up and coming HTML5 standard, earning a score of 328 with 13 bonus points. Opera and Firefox place second and third, at 286 and 255 (respectively). Apple Safari trails behind in fourth with 187 points, while Microsoft's IE9 scores a comparatively poor 130.