That's actually a good thing. I don't see "casual" sites using WebGL any time soon, more likely it'll be professional or purpose built sites (like online design software). Installing another browser will be a very small hassle for someone who wants to use such services online. Microsoft is simply not in the position of deciding which standards will live or die any more.

It's just another nail in the coffin of IE. The sooner we get rid of it, the better.

Actually, it's possible to make WebGL run in IE as well, with a plugin which automatically installs on the users system. Its name is IEWebGL and works quite nice: http://www.iewebgl.com/ CopperCube for example is using this: http://www.ambiera.com/coppercube/faq.html#iewebgl

They like to do this. They stand firm. They hold out and insist that they probably have a better idea. 5 years later... everyone laughs at the browser that is only used by people that either have no choice, or are too old to really understand what they're using. Go ahead Microsoft. Keep making dumb choices. I doubt anyone with a brain even notices.