The April 25 release of a feature-complete Windows Server "Longhorn" beta is a monumental milestone for Microsoft, perhaps more important than the launch of Windows Vista. As the nucleus of Microsoft's enterprise product strategy, Longhorn will likely pull deployments of other products, including Vista. However, uncertainty about the release of the first Vista service pack looms like a dark cloud over future upgrades.

The With the release of Beta 3, Microsoft, in Redmond, Wash., reaffirmed its Longhorn release-to-manufacturing commitment for the second half of 2007. However, officials refused to reaffirm commitment for the release of Vista Service Pack 1. In November, Bob Muglia, Microsoft's senior vice president for server and tools, told eWEEK that Windows Server Longhorn and Vista SP1 would ship "simultaneously."

Read more here about Microsoft's release of the first public beta of Longhorn.

The "It is one source code base," Muglia said. "So, if you follow that model, you have to ship them both at roughly the same time."

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The Simultaneous—or even "roughly the same time"—is no longer Microsoft's position. "It is too early to talk about SP1's delivery, including whether it will be released at the same time as Windows Server code name Longhorn," a Microsoft spokesperson told eWEEK. The statement contradicts Muglia's earlier statement. When pressed, the spokesperson would only further say that there was "no firm date range for SP1."

The The simultaneous release is important for Microsoft and its enterprise customers, said analysts. Longhorn's eventual release will likely set off major software upgrades, including Office 2007 and Vista.

The Laura DiDio, an analyst with the Yankee Group, called the expected phenomenon the "Big Bang." Other analysts' projections of Vista upgrades, including Gartner's, sync well with the Big Bang theory.

The Gartner expects the first major round of Vista deployments to start in the fourth quarter, with most businesses waiting until the second quarter of 2008. The timing is also right for Longhorn's release and potential pull on Windows client upgrades. Many IT organizations are willing to wait for Longhorn so as to coordinate multiple infrastructure upgrades around the same time, DiDio said.

The However, a number of high-profile Microsoft customers, including Intel, have indicated they will hold back major Vista deployments until release of the first service pack. So Longhorn's release isn't a singular event affecting Vista deployments.

The The Big Bang of upgrades hinges as much on Vista SP1's release as Longhorn. Any delay in delivery of Vista SP1 would be an aberration from recent Microsoft operating system development, where Windows client milestones followed Windows Server.

The In 2004, Microsoft reset Vista using fresh code from Windows Server 2003. Microsoft has since developed the client and server software, in tandem, off a single code base.

The As such, Windows desktop and server product releases are fairly coordinated. For example, the 64-bit versions of Windows XP and Windows Server released to manufacturing simultaneously with the release of Windows Server 2003 SP1.

The Vista's development also has closely tracked with Longhorn progress. In December 2005, Microsoft released simultaneous Vista and Longhorn betas. In May 2006, Microsoft simultaneously released new Office 2007, Vista and Longhorn betas.

The Simultaneous release of Longhorn and Vista SP1 would be expected. In addition, positive customer reaction to Longhorn's Beta 3 is fairly favorable for the Big Bang, assuming Vista SP1 is ready.

The "We are very excited about Beta 3," said Juergen Otter, senior Active Directory architect at Siemens, in Munich, Germany. "We love the new features in Active Directory and the improvements to Terminal Server."

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