Windows 8.1 Update 1 has come and gone. The Windows Team are now focused on either a future update for Windows 8.1, or the next major version of Windows, Windows 9. Whilst we are yet to see any leaks of the next iteration of Windows, app logs from various developers are seeing their apps being used on builds higher than the Windows 8.1 RTM. @AngelWZR on Twitter claims that 6.3.9740 has been spotted, from Bellevue in Washington, also known as the home to the Microsoft campus.
The build number is pretty vague - 6.3.9740 could be an internal build of Windows, from any development branch. Since Windows 8.1 Update 1 didn't advance the build number, we assume 9740 is Windows 9, as an Update 2 to Windows 8.1 probably wouldn't advance the build string either. Of course, this is all speculation and nothing is concrete. Pretty much all we can tell from this build number is that the next iteration of Windows, at this currently development stage, still uses Windows NT 6.3. This could easily change in the future, we could see Windows NT 6.4 or even Windows NT 7.0.
So, are you excited to see new build numbers for the next iteration of Windows? We are! Hopefully we'll start seeing new leaks soon, hopefully of the already announced Mini Start and the rumored Metro 2.0 UI coming in Windows 9. Until then, stick around at WinBeta for more news regarding the development of Windows.