Microsoft has rolled out Visual Studio 14 CTP 4 for developers. Visual Studio 14 CTP is a preview for the next major release of Visual Studio. CTPs are intended to promote continuous feedback between early adopters and the Visual Studio development team. You can head over here to read the release notes and download CTP 4.
CTP 4 features all of the features and fixes from previous CTPs, along with ASP.NET vNext tooling and runtime updates, Debugger improvements, and Peek support in the XAML Editor. Microsoft has also rolled out TypeScript 1.1 CTP, which includes the first release of a significantly faster compiler with full TypeScript 1.0 language compatibility. If you are using TypeScript from Visual Studio, you also get full IntelliSense, code navigation, and integrated build. You can see and contribute to the project on GitHub as well.