If you believe the prognostications of the day, this could be the last version of Windows that's a huge, locally running, core set of software running on millions of PCs. The future could involve an operating system with a far simpler code base, perhaps closer in nature to much earlier operating systems, whose primary goal is to interface with hardware. In such a world, the software that provides access to your data and the Internet could be a unified service supplied over the Internet or a network server (or both). As the plumbing of the Internet becomes more advanced, some of the technologies on the desktop may no longer be needed.

Not that I buy any of that. The time of thin clients, at least as previously envisioned, isn't fast approaching. But there can be no doubt that some movement beyond Internet-served applications is likely. There's a reason why Microsoft has scrambled to make Windows Live a reality, and why Ray Ozzie is Gates' heir apparent on the vision front. Any movement away from the proprietary desktop OS paradigm would entail drastic change for Windows versions to come. By the end of this decade, when the next version of Windows will be on the way, it's likely to either a lightweight update or software that's difficult to imagine now. One thing is sure, business needs will be the driving force. If, ah, "lean" clients using open-protocol, open-file format Web-served applications are the direction business heads in, Microsoft will face an enormous challenge.

That's why Windows Vista could be the culmination of Windows, the last in a line before a major shift. And Vista fits that role well. It's not just the best version of Windows ever, it's the best Windows upgrade ever. In other words, it's a bigger advance for this time than other versions of Windows were for their time. Windows 95 is the only one that comes close.

Does that make it better than Apple's Mac OS X? I'm afraid not. OS X is still, all things considered, a better operating system. But OS X is little more than a test tube compared to the vast user base that Windows commands. Vista will have a huge impact on the entire world of computing, while Apple's OS -- which Apple still foolishly insists must run solely on its hardware -- continues to languish as the choice of a paltry few. Microsoft wins again.

Even so, at Beta 2, with its next beta version, RC1, promising to be more than just a bug-fix release candidate, it's way too soon to hand out a final verdict on Windows Vista. It's heading in the right direction, it's filled to overflowing with great new features and functionalities, but we'll make the final call when it's ready to go.