ES6 is not fully implemented in any browser yet, even the specifications are not finalized. Still there are a number of good options for how to use ES6 features today. We use es6ify which relies on Google’s traceur. Together with Browserify and Gulp we transpile our ES6 code to ES5.
There is a long list of features and improvements in EcmaScript 6 (see the ES6 draft or the features supported by Traceur). In this workshop we made a selection of features to go through; template literals, default parameters, arrow functions, destructuring, rest parameters, spread operator and generators.