I was reading this and one sentence caught my eye (emphasis mine): So Ian Hickson, XHTMLs biggest critic, fathered HTML 5, an action-oriented toddler specification that wont reach adulthood until 2022, although some of it can be used today. Is that true? Is that really the HTML 5 development cycle? Why is it taking so long? What makes it so difficult to get right that it won't be final until 11 years from now? 
Why does it take so long to finalize the HTML 5 spec?
html5
The date mentioned for the finalization process was set so far into the future because the standards process for the HTML spec was set up in such a way that it guaranteed wide acceptance of the specification.Some background: there are two standards bodies that work on drafts related to what we commonly refer to as HTML5: the World Wide Web Consortium (W3C), and the Web Hypertext Application Technology Working Group (WHATWG). Prior to July 2012, both groups were working (mostly) together to develop HTML.The main process was to run through a series of milestones:Working Draft:spec is in active development and discussionLast Call Working Draft (LCWD):  spec is mostly complete, and implementors have an opportunity to raise any last objections to the spec before it enters the finalization processCandidate Recommendation:spec is effectively finalized and safe to use for implementors and content authorsRecommendation: two independent, fully-interoperable implementations of the spec have been fully completedThe LCWD milestone began in 2011 and Candidate Recommendation phase was expected to come relatively soon in 2014. It was the last milestone, Recommendation, which required two full implementations of the spec, that would've taken several years and is the reason for the 2022 date.In this model, the first real milestone that concerned content authors (not user agent creators, like browsers) was the LCWD, as the spec was intended to be mostly finalized. Once the LCWD was completed, HTML5 would've reached the Candidate Recommendation milestone, and it would've been a final specification in all but name: you would've been able to implement it with impunity, as the last milestone, Recommendation, would have no effect on the content of the standard and is largely uninteresting to content authors.However, in July 2012, the W3C and WHATWG formalized a split in how the HTML5 draft would be developed. This split, which had been functionally going on for a few years now, sets up two different HTML tracks:A living standard, developed by the WHATWG and simply called HTML, wherein the specification is never fully complete. Reasonable consensus for the standard is established but there is no requirement to implement everything.Periodic, stable snapshots of the standard developed by the W3C as the HTML5 spec. As of September 2012, the W3C is proposing to reach the Recommendation milestone on HTML 5.0 in 2014, with point snapshots every two years (e.g., HTML 5.1 in 2016).Because of the former, HTML5, as we've come to understand it, is usable now. Unfortunately, because it is a living standard, using it as a content author requires understanding each user agent's implementation.