Update: Microsoft should either stick to a decision or make a better one in the first place. After receiving some expected backlash for not distributing the final version of Windows 8.1 to developers via MSDN and Technet, today they reversed course. Windows 8.1 RTM is now available for downloads to developers along with Windows Server 2012 R2 RTM and Visual Studio 2013 Release Candidate.
Original story follows below:
Earlier in the week, Microsoft revealed that Windows 8.1 had been released to their hardware partners, also confirming rumors that the operating system would not be available for developers and IT professionals through TechNet and MSDN until the general availability date, October 18th.
This annoyed a number of devs, who claim that it's essential for the RTM code to be available through MSDN and TechNet before the general release, so that applications can be tested and made compatible with any OS changes. Microsoft's Brandon LeBlanc stated that in withholding Windows 8.1 from developer channels, Microsoft can continue to "put the finishing touches on Windows 8.1 to ensure a quality experience at general availability for (all) customers."
In response to a lack of RTM code for developers, OEMs - the only people who currently have official access to the final version of Windows 8.1 - have leaked basically every copy of the Windows 8.1 RTM to the web. Neowin reports that the English Windows 8.1 Pro x86 and x64 builds have leaked to the internet, courtesy of Russian leaker WZOR.
As well as the Windows 8.1 builds, RTM copies of Windows Server 2012 R2, Essentials, Enterprise, Hyper-V, and Foundation Storage have leaked. All editions are apparently untouched, Microsoft images of the operating system: the same copies that would presumably be available on MSDN and TechNet if Microsoft had released them there.
While copies of the Windows 8.1 RTM are floating around on the internet, Microsoft will officially release the operating system on October 18th, where it will be delivered as a free update through the Windows Store to existing Windows 8 users. The update introduces a range of new features, including enhanced search and multi-tasking, an improved Start screen with new customization options, and optimizations for smaller tablets.