Via the official Windows blog, Microsoft has confirmed that Windows 8.1 (formerly known as Windows Blue) will be a free update for those running the current Windows 8 operating system. Many had suspected that the Redmond company might try its hand at Apple’s system of meager updates for a minimal fee, but, as per the blog post, the update will in fact be called Windows 8.1, and will be offered as “a free update to Windows 8 for consumers through the Windows Store.”

Windows 8 has certainly divided opinion among PC users, with some users having been vocally critical of the tiled, so-called Metro interface that Microsoft decided to opt for. Traditionalists have been particularly unimpressed with the new Start menu, which, while adept for tablet use, can confuse the everyday, desktop Windows user. According to sources of TheVerge, Microsoft is testing current builds of Windows 8.1 inclusive of an option for users to boot into the much familiar desktop screen.

The recently confirmed Windows Blue appears to be the internal name for Windows 8.1 rather than Windows 9, according to multiple sources. More details on this after the jump!

A short while ago, we learned that Microsoft’s annual BUILD developer conference would be held this year on June 26th, at the Moscone Center in San Francisco. Further to that report, TheVerge has learned that the Redmond company will use the event as a platform to release a Public Preview of the next release of Windows, codenamed Windows Blue. Citing “sources familiar with Microsoft’s plans”, the report also adds that work on the preview version is already underway, and will be available to download in much the same way the Windows 8 Developer, Consumer, and Release Previews were dropped at numerous intervals last year.

Since the release of Windows 8 last year, Microsoft has not stopped the development of Windows for a second. More evidence of an upcoming version of Windows, code named “Blue”, have emerged as a new build has leaked onto the Web. While the release looks overall similar to Windows 8, there have been quite a few changes that are worthy of note.

Microsoft has been preparing its Windows Blue updates for quite a while now, and screenshots of some of the latest developments have begun to emerge via several sites dedicated to the Redmond company’s flagship operating system. The screenies reveal two different builds of what is referred to internally as Windows Blue, and although build numbers are unconfirmed, TheVerge has learned that Microsoft recently pushed its NT kernel up to 6.3.

Such is the manner in which technology moves nowadays, no sooner is one major release out of the way, do consumers, analysts and enthusiasts in general begin nattering about what’s up next. Windows 8 has been in our faces for the entire year, after Microsoft dropped the Developer Preview to the public in an unprecedented move, but despite not releasing for another two-and-a-half months, the successor to Windows 8 has already got chins wagging.