Ok... I remembered that I have a blog, and what a surprise that I realized that almost a year ago was my last post, and It was about WebGL, which were going to be by default in the next Firefox 4.0. So what happened after one year, well... firefox 4.0, and it had WebGL by default, also Chrome, and may be in the future Safari with the next operative system of Lion, and Opera.
WebGL, my experience is really good, a very fast way to make good graphics in the Web, how good? and how fast, ok... examples:
I made a lot of work in WebGL... may be you should check the volume rendering code.
Finally... emscripten... a very good project... it has some problems in the architecture... but... I think is a the correct way to get Rich Apps to the web.