QuoteLikely by the end of 2011, the W3C will issue a second last-call version and begin a second round of refinements.
In the second quarter of 2012, a new phase begins, in which "implementors" of the specification--browser makers, essentially--provide feedback. During this phase, the W3C concentrates on a suite of thousands of tests to see if implementations of HTML5 really do get the same results when interpreting a Web page's code.
The culmination of this phase is a "candidate recommendation" of the HTML5 spec and at least two "interoperable implementations"--in other words, two different browsers that produce the same results on the test cases. The implementors' feedback is scheduled for completion by the first quarter of 2014.