TORONTO — There are 600 million Windows PCs today, according to Microsoft. But by 2010, there will be more than 1 billion of them, company officials claim.

Will Poole, the head of Microsoft's Windows client business, made these bold predictions here at the annual Microsoft worldwide partner conference in his keynote on Monday morning.

Poole said Microsoft expects the demand to come from enterprises in developed countries, all sizes of companies in developing markets and from OEMs that tailor Windows for specific markets.

Many industry watchers have talked about the Windows desktop market as being a saturated one, with little potential for the huge unit and revenue growth of the past. But that's not the picture Microsoft's painting.

"PC replacements are at the top of what IT will be spending on this year," Poole predicted.

According to Microsoft's figures, 35 percent of enterprises are still running Windows 9X-based versions of Windows (like Windows 98 and Windows Millennium Edition) and/or NT Workstation. These users are ripe for upgrades, Poole said.

At Microsoft has been making a concerted effort to develop cut-rate Windows bundles for overseas users. The Thai version of the bundle is known as "XP Starter Kit." Microsoft is selling a similar bundle in Malaysia and has hinted more are on the way.

To help partners push Windows out to these companies, Microsoft is updating its Desktop Deployment initiative, which it introduced last year. It is rolling out two new collections of blueprints, methodologies and tools — called "Solution Accelerators," in Microsoft parlance — to help partners set up and configure Windows XP systems for customers in minutes per machine, instead of hours.

Microsoft's demonstration of the "Zero Touch" version of its Windows XP deployment tool drew resounding applause from keynote attendees.

"We need to overcome this legacy 'good enough' perception," Poole said, whereby users running older operating-system releases don't see a compelling reason to upgrade.

Poole also highlighted Windows XP Service Pack 2 (XP SP2), the Windows XP refresh designed primarily to deliver new security features to customers. The product is currently in beta test among more than 800,000 individuals total, Poole said.

Microsoft executives had said to expect Microsoft to release SP2 to manufacturing in late July. Today at the conference, Poole said Microsoft is planning to finalize the product a month later, in August. He said Microsoft will deliver the final XP SP2 release to customers via its Windows Update site; CDs (for those on slower bandwidth connections) and via OEMs and system builders who will preload the release on their systems within 90 days from the time the SP2 release goes gold.

Poole also showed off a new Windows Marketplace portal, which Microsoft intends to use to help customers more easily find third-party Windows software and services. Via the Marketplace, which is being hosted by Download.com, Microsoft will showcase more than 100,000 drivers, applications and peripherals. It also will provide users with access to community ratings, reviews and discussion areas on various products.

The first version of the Marketplace is due out this fall. Microsoft plans to make it accessible via the Windows Start button, as well as by a link in Internet Explorer.

Poole said Microsoft is still on track to deliver a first Longhorn beta release in the first half of calendar 2005. Microsoft executives at the partner conference are still talking publicly about Longhorn's final delivery date as 2006.