Mary Jo Foley for ZDNet on “Windows Blue”, the first major upgrade to Windows 8 (yes, they’re going to update Windows 8 already):
According to one of the screen shot leakers, the WZor team (via Winaero.com), there’s a rumor that Windows Blue is based on Windows 6.3. I’m hearing from one of my sources that this information is correct. It’s version 6.3 for the same reason Windows 7 was version 6.1: It’s the version number reported to apps when they query the new platform so that apps know they are running on a new Windows release.
Windows Blue is believed to be the first of a number of annual operating system updates to Windows 8. There also is a Windows Phone Blue in the works that is expected to have the same core code as Windows Blue. (But, just like the Windows Phone 8 operating system, which was version 8.0, the Windows Phone Blue core build number will likely be something different from Windows 6.3.)
So Windows Blue is actually Windows 6.3. Windows 7 was Windows 6.1. Windows Phone 8 is version 8.0. This is all just so perfectly Microsoft. As if the consumer branding wasn’t bad enough, the internal numerical scheme is a clusterfuck as well.