Major changes:

• add import() as Code Splitting construct. It should be used instead of System.import when possible. System.import will be deprecated in webpack 2 release (removed in webpack 3) as it's behavior is incorrect according to the spec.
• *.json files are now supported without the json-loader. You may still use it. It's not a breaking change.
• webpack will now show performance warnings when bundle size is too big. You can disable them with performance.hints = false. It recommended to disable them in development but leave them enabled in production.

Bugfixes:

• Generate equal code on each platform when using node.js modules, module, process, global, etc.
• CLI: Fixes --module-bind for the -loader change
• Validation: externals now allows boolean values
• Loaders: Complex options are now correctly passed when using remainingRequest like with the style-loader
• Fixes a event leak when using watch mode
• Stats: exclude now only tests resource and not complete identifier
• Fixes bug related to export * from ...
• CLI: Fix behavior of --cache and --no-cache
• It's now possible to combine webpack ES2015 modules with babel ES2015 modules

Features:

• add output.strictModuleExceptionHandling option which handles exceptions in modules correctly, but with less performance. The more performant variant is enabled by default.
• Template strings are now allowed at locations where expressions are allowed. import(./template/${template})
• Allow to match rules on resourceQuery
• add __webpack_nonce__ to set nonce for chunk loading script tags
• Improve tree shaking for import *

Performance:

• Cache some expensive stuff

🎄 We are approaching the first Release Candidate...