I wouldn't hold my breath for WebGL appearing even in IE11. Whatever Microsoft is saying, the "security" of WebGL is not the main reason why Microsoft is not the adopting it - not even close. Just like security is also not the main reason why Apple is not allowing other JS engines on iOS.

The lack of support for XP, which is still like 40% of the market, means Chrome is still by far the most secure browser on XP, which is something companies who aren't going to get new PC's and Windows licenses anytime soon should start considering.

No full screen API, no Web Audio API, and no WebRTC (and no Opus either) are also very regrettable omissions.