The latest preview of VS2015 seeks to rectify some stability issues introduced in CTP5 while providing another round of new tools and refinements. These new features should bring something new to everyone using the application.
A benefit for developers utilizing multiple Microsoft online services is improved handling of credentials. Given that developers working on the Microsoft platform will typically have several different accounts (VS Online, Azure, MSDN, etc) having to enter them individually each time those services are accessed is time consuming and frustrating. CTP6 will now prompt for this login once and will forward them to each service as they are accessed.
CodeLens has been expanded to show details about the Git commit history for the code stored in Git repositories and similar information for work items in TFS. This includes a timeline for the changes made and who committed them. Being able to clearly see this metadata can make it easier to identify who may be familiar with the code and/or if a recent change caused undesired behavior.
NuGet support has been raised to version 3 Beta, which itself provides several new features. However early reports indicate that this release is not yet stable, and so curious users should wait until additional stability is introduced. When it is more stable, users can expect to find new Powershell cmdlets, adding the ability to build NuGet with NuGet itself, and a revised dialog box for selecting NuGet packages to install while in Visual Studio.
Something to keep in mind with this CTP is that the legacy JIT compiler for .NET is not available. In this release the next-generation JIT (RyuJIT) is the only one available. Microsoft states that the option to use the legacy JIT will return in the next CTP.
The CTP is available for download in both standalone ISO formats and a web-based installer.