Earlier this week, Microsoft leaked a Windows 10 for PCs build, build 10537. We also got to see the leaked release notes. There’s not a whole lot new, like it was in the earlier days of the Windows 10 Technical Preview, but there was a good amount.
This is Threshold 2. If you recall, Threshold was the codename for Windows 10. They were going to release it in October but decided to push it up to July 29. It stands to reason that Threshold 2 is what they would have released had they waited.