AutoCAD 2010 Help is now available in HTML online as well as many other AutoCAD 2010 learning and training resources free. I believe this is just one step towards something even more exciting in the future for documentation, but more on that if and when it materializes.
http://www.autodesk.com/autocad-help
More resources
Web-based Training and Help for AutoCAD 2010 can be accessed from the following resources
Learning Path.
Cheers,
Shaan