The goal is to make the native authoring and use of declarative XML-based X3D scenes as natural and well-supported for HTML V5 authors similar to the support provided for Scalable Vector Graphics (SVG) and Mathematical Markup Language (MathML).
Due to the large interest there were several recent discussions, meeting and BoFs related to this project. Johannes Behr's slide set from SIGGRAPH 2010 X3D/HTML5 BoF and the Khronos WebGL BoF sessions is available on request.
This effort has strategic importance for Web3D and indeed for all 3D graphics, since X3D is an interchange format for a wide variety of models. We intend to establish a solid foundation for X3D to properly support 3D graphics in HTML V5. Additional information on the X3D/HTML5 Web3D Working group and their current initiatives and efforts is available in our Wiki.