Note: While reading the comment's Lachlan's ALA article, I saw the same questions being asked. I figured it'd be good to keep a list of the questions and to start drafting answers.
What is the goal of HTML 5?
- more interoperability when recovering from errors - http://www.w3.org/QA/2007/07/why-html-5-matters.html
- codify existing best practices... "pave the cowpaths"
- allow HTML to better serve the needs of Web Applications
Why will it take ten to fifteen years? Will it take that long? What is the time frame?
From Lachlan's A List Apart Answer
The 10-15 year time frame includes the time required stabilize the spec, produce the test suite containing thousands of tests and achieve interoperable implementations. Browsers are expected to implement HTML5 during this time, not wait until after. Indeed, they have already begun, which is why we’re already seeing early implementations of video, audio, and we have had canvas for a long time already.
For comparison, look at CSS 2.1. It’s been 10 years since CSS2 was started and that’s still only a candidate recommendation. However, it’s been relatively stable for a few years now, while still being updated based on implementation feedback.
The goal set down in the charter is for HTML 5 to reach W3C Recommendation status by Q3 2010.
Who is involved in the HTML 5 WG?
As of 05 Decemeber, 2007, there are 70 participants from 27 W3C member organizations and 422 Invited Experts.
Who has started making implementations of HTML 5?
From Shawn Medero's comment in Lachlan's ALA Article...
- <canvas> is implemented in Firefox, Opera (& Opera Mobile), and Safari (& Mobile Safari).
- <video> is implemented in the Opera 9.5 betas and in the WebKit nightlies.
- WebKit nightlies implement HTML 5’s Offline storage API
- There is an open-source HTML 5 parsing engine written in Python & Ruby