Brrrrrrr! Do you feel that? I thought summer was upon us -- but not in Redmond, it seems.

Yesterday, tech-industry researcher Gartner (NYSE:IT) published a report that predicted that Microsoft's (NASDAQ:MSFT) new Windows Vista operating system wouldn't reach the mass market till at least March 2007. Investors have left for warmer climes, dropping Mr. Softy's shares by 2.5% in today's trading.

For its part, the House of Gates insists that it's on its new schedule. But the Gartner report isn't easily dismissed. It points to prior upgrades of Windows for support. For example, Windows 2000, a major upgrade of the platform, ultimately took 16 months between its second beta and final release in December 1999. Vista hasn't reached the so-called "beta 2" stage. It is expected to do so during the current quarter, which should close on June 30.

That's where Gartner's thesis proves interesting. Think about it: 16 months from June is October 2007. Ouch. Gartner, thankfully, offers a more optimistic view, estimating that it will take nine to 12 months for Mr. Softy to fix bugs found during the second beta. That's where the March 2007 target comes from.

Conspiracy theorists pro and con are doubtlessly digging into the Gartner report with a fervor generally reserved for The Da Vinci Code. For others, the ones dumping the stock today, it might not seem worth the time. I find it remarkable that it's become easy to write off Microsoft, but this chart suggests otherwise.

Perhaps permafrost has settled around Mr. Softy's Redmond headquarters. Maybe it is destined to be a permanent second fiddle to Google (NASDAQ:GOOG). And maybe users have finally decided they don't need Windows on 90% of their computers. Maybe.

But would any of those outcomes really be so bad? How many companies do you know that have made billions playing second fiddle? And how many of them have existed in tech? How about Apple (NASDAQ:AAPL) in PCs? How about IBM (NYSE:IBM) in storage and databases? How about Advanced Micro Devices (NYSE:AMD) in semiconductors?

Here's the bottom line: I get it if you don't want to buy Microsoft, even at these prices. But if you're selling, I've got to question at least your logic, and perhaps your sanity. It's maybe round five of what could be a 100-round bout, and Mr. Softy has billions still in the bank and some of the world's smartest people on the payroll. Betting against them now isn't Foolish -- it's foolish.

Microsoft is a Motley Fool Inside Value selection. Get anall-access passto Inside Value to find out which other stocks are helping chief advisor Philip Durell beat the market by nearly 4%. You'll also receive instructive lessons on valuation and company analysis. Give Inside Value a try; it's free for 30 days.

Fool contributor Tim Beyers can hardly believe the beating Microsoft is taking. Is this for real? Tim didn't own shares in any of the companies mentioned in this story at the time of publication. You can find out which stocks he owns by checking Tim's Fool profile . The Motley Fool has an ironclad disclosure policy .