I don't understand why people keep falling for this crap. Microsoft will do the best that it possibly can to disrupt WebGL with compatibility and other issues, just as it has always done with every key aspect of web technology. This li brary is the latest example. They could have easily made improvements to Three.js or some other existing library that was tested on other browsers but they did not. There are too many billions of dollars on the line. 3d gaming in the browser means the end of the Windows PC monopoly and Microsoft knows that whether the rest of you do or not. No I'm not exaggerating.
Where does it say this? Demos work fine in Chrome for me, at least.
Regarding the missing collisions: ThreeJS focuses on the 3D part of a game engine only. If you want collisions, you need to add a physic engine.
There's a couple of them out there - I would recommend CannonJS and there is a working ThreeJS FPS with WASD and collisions here: https://web3dblog.wordpress.com/2013/01/07/source-code-of-th...
BTW...Babylon.js works in all 3 of the major browsers, and performs best in Firefox, not IE10.
Syntax seems pretty similar, which is not terribly surprising.