But.. they're putting OpenGL ES in HTML5's canvas as is.
Quoting from: http://www.w3.org/TR/html5/the-canvas.html
"A future version of this specification will probably define a 3d context (probably based on the OpenGL ES API)."
It's JavaScript. View Source is your friend. Now what I don't see is any mention of a license. In that respect, yes, I agree, I hope they release this under an open-source license.
Quoting from: http://www.w3.org/TR/html5/the-canvas.html "A future version of this specification will probably define a 3d context (probably based on the OpenGL ES API)."