Screenshots of an early partner build of Microsoft's next major update to Windows, codenamed "Windows Blue," have been leaked to the web. At this point it's way too premature to call it an early build of Windows 9; Windows 8 "Service Pack 1" sounds more plausible. Interestingly, the screenshots reveal two contrasting specifications. First, the OS is carrying a Windows NT kernel version 6.3 (current Windows 8 features kernel 6.2); yet the build number hasn't deviated from the 9000 series, at build 9364. Microsoft doesn't usually change kernel version number with service packs, yet build numbering typically changes when the company is working on newer versions of Windows (say, Windows 9, in this case).
The screenshots reveal a slightly tweaked Start screen featuring tiny tiles (a là Windows Phone 7.8+), quicker multi-tasking within the modern UI, and between modern UI apps, without switching to the Desktop, and far more customization options for the modern UI. A bolt out of the "Blue" is a screenshot of next-generation Internet Explorer 11 web-browser, which doesn't appear to change the user-interface at all, compared to today's Internet Explorer 10, but that shouldn't matter. Most builds of MSIE at their earliest pre-launch builds feature UI carried over by their predecessors.
The Windows Blue leak appears to be emanating by a source emanating from France. The build only supports the 32-bit x86 machine architecture, which should give most authorized partners and developers the chance to try out the OS, without any real value in leaking it (unless you're happy with <4 GB of memory). The unique employee ID is clearly mentioned in its disc image (.iso) filename of "9364.0.FBL_PARTNER_OUT13.130315-2105_X86FRE_CLIENT." The following are two videos of the software in action.