2.1

• Investigate Function bind operator
• Support for project references
• readonly modifier
• Investigate nominal typing support
• Refactoring support in Language Service API
• Flattening declarations

2.0

• Switch to a transformation-based emitter
• async/await support for ES5/ES3
• Support ES7 object property spread and rest
• Specifying this types for functions
• Type guards on property access
• Switch type guards
• Support type-checking of computed properties for constants and Symbols
• Variadic types
• Ambient decorators
• Deprecated decorator
• Conditional decorator
• Decorators for function expressions/arrow functions
• Support for node register hook
• Glob support in tsconfig.json
• Quick fixes support in language service API
• tsd integration in tsserver/language service API
• Extract type information from JSDoc in js files
• Improve lib.d.ts modularity
• Support for external helpers library

1.8

• Allow JavaScript in TypeScript compilations with --allowjs
• Allow captured let/const in loops
• Flag unreachable code
• Concatenate module output with --outFile
• Accept comments in tsconfig.json
• Stylize error messages in terminal output with --pretty
• Support for --outFile with named pipes, sockets, and special devices
• Support computed property with literal names
• String literal types
• Stateless Functional Components in JSX
• Improved union/intersection type inference
• Support for F-Bounded Polymorphism
• Support full path for -project/-p parameter
• Support for default import interop with SystemJS using --allowSyntheticDefaultImports
• Recognize prototype assignments in JavaScript files
• Use path mappings in module resolution
• Augmenting global/module scope from other modules
• Use tsconfig.json as higher priority source of configuration in Visual Studio
• this-based type guards

1.7

• ES7 exponentiation operator
• Polymorphic this type
• Support --module with --target es6
• Support for decorators when targeting ES3
• async/await support for ES6 (Node v4)
• Improved checking of destructuring with literal initializers

1.6

• ES6 Generators
• Local types
• Generic type aliases
• Expressions in class extends clauses
• Class expressions
• exclude property in tsconfig.json
• User defined type guard functions
• External module resolution enhancements
• JSX support
• Intersection types
• abstract classes and methods
• Strict object literal assignment checking
• Declaration merging for classes and interfaces
• New --init

1.5

• Support for Destructuring
• Support for Spread Operator
• Support for ES6 Modules
• Support for for..of
• Support for ES6 Unicode specification
• Support for Symbols
• Support for Computed properties
• Support for tsconfig.json files
• Support for let and const in ES3/ES5
• Support for tagged templates in ES3/ES5
• Expose a new editor interface through TS Server
• Support for ES7 Decorators proposal
• Support for Decorator type metadata
• New --rootDir
• New ts.transpile API
• Support --module umd
• Support --module system
• New --noEmitHelpers
• New --inlineSourceMap
• New --inlineSources
• New --newLine
• New --isolatedModules
• Support for new namespace keyword
• Support for tsconfig.json in Visual Studio 2015
• Improved template literal highlighting in Visual Studio 2013

1.4

• Support for Union Types and Type Guards
• New --noEmitOnError
• New --target ES6
• Support for Let and Const
• Support for Template Literals
• Library typings for ES6
• Support for Const enums
• Export Language Service public API

1.3

• Language service re-write to target new compiler
• Support for protected members in classes
• Support for Tuple Types