Acid 3 is a test of dynamic browser capabilities which exists to encourage browser vendors to focus on interoperability. It's a hard browser test of 100 tasks of almost all area. Acid3 now includes DOM Scripting capability.
Browser needs to be at default settings (zoom, font changing, custom styles will do "bad numbers"). There is no browser who passed the test with 100%, but some of the results are interesting. If the % numbers says 15% that means that he passed 15 of 100 Acid3 tasks.
Internet Explorer 5.5 / Windows 2000 » 13%
Internet Explorer 7.0 / Windows XP » 12%
Internet Explorer 6.0 / Windows XP » 12%
The oldest version of Internet Explorer, version 5.5 (July 2000) have better results of the new one, IE 7. Microsoft!! More is better!!
Safari WebKit Nightly (r30881) / Mac OS X 10.5.2 » 90%
Firefox 2.0.0.12 / Mac OS X 10.5.2 » 52%
Opera 9.26 / Mac OS X 10.5.2 » 46%
This results make me sad, because, Microsoft, is producing OS that have huge market share, and has minimum interest for improving his browser quality. Now they are testing Internet explorer 8, but until version 49, I don’t think that they are capable of making anything better before.