which is not good news!!!
they might work on IE using the "chrome frame" plugin if you pop that up for teh user to install.
i can't understand how come safari does not support webgl, they just release v6 recently
My lab director just spent a week out at Google (Mountain View, CA) and he returned utterly convinced of the future of WebGL and HTML5. Google is doing some insanely amazing work with WebGL and they will be pushing it HARD.
Others will come around. Anything worth doing involves risk and some manner of faith.