In the aftermath of Microsoft's decision to use the Windows 7 codename as the final name for that product, a weird backlash has grown online: Why is Microsoft describing this release as the "seventh release of Windows" when it clearly is no such thing?

"'Windows 7 just makes sense,'" Microsoft corporate vice president Mike Nash wrote in a Microsoft corporate blog Tuesday. "Simply put, this is the seventh release of Windows."

It turns out it's not really that simple. And many tech bloggers are calling Microsoft's bluff, stepping through various versions of Windows in an attempt to justify the logic of the Windows 7 name. But faux indignation aside, this is hardly an intellectual exercise. No matter how you count it, Windows 7 is not the seventh release of Windows.

The problem, of course, is that Microsoft has confusingly used three different branding types for its client versions of Windows. It has used year names (Windows 95, 98), version numbers (Windows 3.1, Windows 3.11), and so-called "aspirational" names--Windows XP and Vista--that are as made up as the word "aspirational."

Looking at just the major versions of Windows, you will find Windows 1.x, 2.x, 3.x, 95, NT 4.0, 2000, XP, and Vista, making Windows 7 the ninth version of Windows. But there have been far more versions of Windows than those--Windows 98, Windows Millennium Edition (Me), Windows NT 3.51, and so on--not to mention supposedly minor versions like Windows 3.1 which were, in fact, huge releases.

Looking at version numbers, things get even more complex, with even more Windows versions. It doesn't help that there were two major Windows product families over the years, starting with the DOS-based "classic" Windows family that ended with Windows Me and the NT family of products that started with version 3.1 to keep it in line with the classic Windows version of the day. Confusing? Yes.

Responding to the criticisms, Mr. Nash followed up his original post and tried to explain how Microsoft arrived at "the seventh release of Windows." It's a bit of tortured logic, where XP (version 5.1) is not counted as a major version while Windows 7 (version 6.1) is. The company would have been better off simply stating the obvious, and what I feel is the real reason for using the Windows 7 moniker: It's simple, and elegant, and we like it.

Microsoft is positioning Windows 7 as a major release of the OS though they've yet to justify that description. Its version number--6.1--hints at what Windows 7 really is, an evolutionary update to the major release called Windows Vista, which was version 6.0. Presumably, the company will add enough end user functionality to the product to make it as interesting as Windows XP, a product that rose well above the meager implications of its own version number.