It appears that the joy of major browsers complying with Acid2 is going to be short-lived, as the Web Standards Project (WaSP) announced yesterday that the Acid3 test designed to expose flaws in the implementation of mature web standards has been released.
Unlike the first acid test, which focused on the box model, and the second acid test, which covered a broad variety of basic HTML and CSS features, Acid3 covers everything from HTTP, HTML, CSS, SVG and XML, all the way through ECMAScript and DOM, both critical requirements for any modern web application. Currently, none of today's browsers is able to correctly render the Acid3 test, with most of them scoring between 40 and 60 on a 100-point scale. This shouldn't be too alarming, though, as the Acid tests are designed to measure standards to aspire to, as opposed to what's current.