I the Acid 3 test even relevant now? The Acid 2 test seem to make browser strive to be semi Standards-compliant and in a very forward looking way. No browser was suppose to pass the Acid 2 test for a wile it was a test like the x-prize. The Acid 2 test was to expose web page rendering flaws in browsers and applications that render HTML code. It was to help expose the need to drive standards in a very entropic environment.
For grown on the web to work there needs to be some underlying standards, but information and innovation occur so quickly that there is not a necessity for all parts to be standardized because they will change and die out to quickly.
The Acid 3 test seems to have lost some relevance as to the Acid 2 test. Browsers seem to have raced to pass the test not to realize the ideas and goals of standardization. they raced blindly to be the first to pass and not to increase the usability of the browser or accessibility for those that are visually impaired. Browsers makers have missed out on the opportunity to understand what standards are needed and are forming and those that need to be let by the wayside. Instead they all say look at me I passed a standards test.