Microsoft's Internet Explorer 9 (IE9) won as the only browser with full HTML5 compliance.
A test run was recently conducted by the Worldwide Web Consortium (W3C), the official organization that develops web standards, that determines a browser's compliance to HTML5. Furthermore, this organization's test is considered as a gold standard. Based on the W3C's findings, it was clearly Microsoft's IE9 complies with all of HTML5's standards.
As for the other browsers, Firefox 4 has shown slight trailing during the test, whereas Chrome 7 and Safari 5 were both left behind. Due to this, IE9 has been considered as a game changer for this particular test.
Despite of numerous complaints after IE9's first release, Microsoft did their best to improve this particular browser. Mainly, the company based all the developments they did from all of the complaints they have heard from the community, users and web developers. This time, Microsoft triumphed by winning this test.
Nowadays, interoperability is one of the most critical problems that web designers normally face. This allows a website to be designed as well as to work well on numerous browsers without having problems on compatibility issues. To make all of this possible, the key would be the compliance to the web standards. Also, experts say that good test suites drive interoperability. It is the key of making sure that web standards are strictly, correctly and consistently implemented. W3C stated that expect more tests encourages more interoperability.
As for the result of the test, W3C set a page where people can view the findings of this result. People can view the result on this page: http://test.w3.org/html/tests/reporting/report.htm