The Windows 10 Creators Update is not even generally available yet, but the Windows Insider Program surprised enthusiast today with an early build of the next version of company's flagship operating system. Only the PC build has been released in x86 and x64 architectures. The latest build number is 16170, a major jump from the RTM release, 15063, for the Creators Update.

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Today we are excited to be releasing a new build from our Development Branch! Windows 10 Insider Preview Build 16170 for PC has been released to Windows Insiders in the Fast ring. As we mentioned earlier this week, you won’t see many big noticeable changes or new features in new builds just yet. That’s because right now, we’re focused on making some refinements to OneCore and doing some code refactoring and other engineering work that is necessary to make sure OneCore is optimally structured for teams to start checking in code. This also means more bugs and other issues that could be slightly more painful to live with – so check your Windows Insider Program settings! Source

As noted, early adopters likely won't see anything new, but for users anxious to participate in the development of Windows 10, this is the place to be. If you are not ready to start playing with a new build, especially a buggy early build such as Redstone 3, you should switch to the slow or release preview rings or stop Windows Insider Builds all together. To do that, click Start > Settings > Update & security > Windows Insider Program and moving to the Slow or Release Preview rings.

It will probably be a while before we start seeing anything substantially new. Some features that did not make it in the Creators Update such as the My People app, 3D Capture app are likely to show up this time. Rumor is a new user experience is planned for Redstone 3, called Project Neon. Expect Microsoft to double down on flagship features and technologies such as Cortana, Gaming and Mixed Reality. I'll be loading up this build in a VM just to see what its like. If I find anything interesting, I will let you know.