Chrome only.

It's worth going through the video to get to the back-end tech demo (https://www.justareflektor.com/tech) where you can plug the video effect components together and modify all the control parameters in real time in the browser:

e.g. I just made http://goo.gl/5l7B5a (the original urls are very long and have non HN friendly characters)

Yes - it's actually worth enabling the webcam to play with this.

I have enjoyed all of the Google/Arcade Fire collaboration videos, especially this one from a while ago, where (spoiler) you are shown your childhood house on Google Maps at the end: http://www.chromeexperiments.com/arcadefire/

It's always interesting to see experiments with art and technology like this (especially with music I enjoy!).

Pretty neat, but didn't work with my Surface or Windows Phone 8 device. What role does the phone/tablet play? The webcam worked, though.

This isn't the first time Arcade Fire has done some neat stuff with Chrome, either: http://thewildernessdowntown.com/