see https://webpack.js.org for the new documentation (currently work in progress)

• native ES6 import, export and System.import
• Tree Shaking for ES6
• Needs Promise polyfill in old browsers (only if you're using code splitting)
• chunk error handling
• Many plugins now take options objects instead of multiple parameters
• config can be a function and --env
• Removed deprecated argument configs (except with one argument shortcut if possible)
• loaders now match resourcePath instead of resource with query
• webpack config can return a Promise
• -p sets NODE_ENV = "production"
• the uglifyjs plugin no longer minimize other assets
• there is the LoaderOptionsPlugin now
• webpackfile.js is now also supported
• added HashedModuleIdsPlugin

• documentation

beta: end 2013, stable: early 2014

• Bugfixes
• updates to loaders

• Hot Code Replacement
• Some more cool features