They use the IE 9 beta, Firefox 4 beta, but Opera 10.60 and not the Opera 11 beta ...
The w3c page does include Opera 11 strangely enough, which is just about on par with IE9:
http://test.w3.org/html/tests/reporting/report.htm
For HTML5 they both have 100%
Personally, I find CSS3 more interesting than HTML5 ...