With the release of Firefox 3, two of the three major web browsers, Firefox and Opera, will have passed the test. This would leave only the great Internet Explorer not passing the test. I would give IE at least until version nine before we see any smiling faces.
Acid2 is a test made by the Web Standards Project to tell if browsers render CSS the way it’s supposed to be done. If a browser passes, it means that it will be a designer’s best friend and render CSS according to the standards set by the W3C.