Microsoft chairman Bill Gates has confirmed one of the IT world's worst-kept secrets: Longhorn will officially be called Windows Server 2008.

Gates made the announcement at Microsoft's 16th annual Windows Hardware Engineering Conference (WinHEC), but he did not shed any additional light on when the server will ship. He said the date remains "the second half of 2007."

The date is key because it also will bring the first public beta of Microsoft's new virtualisation technology, Windows Server Virtualisation (WSV). Last week, Microsoft announced the revised ship date of the WSV public beta and tied it to Longhorn and that certain features were being eliminated in the first version.

Gates introduced the Windows Server 2008 name and joked that Microsoft was going with another creative name and then made a similar crack when he showed a picture of the packaging, which looks just like the Windows Vista packaging.

Gates also used what will be his last appearance at WinHEC before he becomes a part-time employee in July 2008, to tout market acceptance of Vista, demo security and policy features on Windows Server 2008, show a range of next generation mobile devices, and demo Home Server and Windows Rally technology for creating a wireless network for sharing data and video.

Gates highlighted the fact that the recently released Beta 3 of Windows Server 2008 for the first time includes the capability to have different password policies for different users without having to control those features from separate domain controllers.

Gates also looked into the future that it said will be marked by 64-bit processors on servers, desktops and devices, an explosion in available computing form factors, natural user interfaces, unified communications and software plus services.

In addition, he said the Microsoft has shipped 40 million copies of Vista, more than double the number of XP copies shipped in its first 100 days.

"The reaction has been very strong," Gates said. Microsoft thought Vista "would open up a new level of ambition, and that is happening," he told the gathered hardware partners.

Microsoft had previously said that it had sold 20 million copies of Windows in its first month after its consumer launch in late January. That, it claimed, doubled the pace of Windows XP, which sold 17 million copies after the first two months of launch in late 2001.

In an interview last Friday, Kevin Kutz, a director in the Windows client division, said Microsoft's sales figures include copies of Vista shipped to retail shops, licences ordered by hardware makers for pre-installation on PCs, as well as coupons given to customers for free Vista upgrades if they bought a Windows PC in late October or afterwards.

Kutz did not disclose how much that last factor contributed to Microsoft's Vista sales. He denied suggestions that Microsoft's calculation method was designed to make Vista sales look better.

"We tried to be as absolutely consistent as we could," he said.

Kutz also denied that Microsoft was covertly offering incentives to partners to order as many Vista licences as early as possible, or otherwise engaging in "channel stuffing."

"Market momentum is strong, and consumer response is good," he said.

In terms of the future, Gates said by 2008 all servers, desktops and devices would use 64-bit processors.

"What does this mean for the industry," Gates asked. "It allows us to have lots of memory," including advanced visual and business intelligence."

He said Microsoft is working on those concepts.

Gates also showed a range of concept devices developed by design-school students, including a tablet form factor and ones with catchy names, such as Yummy Kitchen Connect, which was a small screen that attaches to a refrigerator.

He also said Microsoft would develop natural-language interfaces, such as speech, that would show up on a range of devices.

"When you scale down the size of things, the need to complement keyboard input becomes increasingly important."

He said the future would also be marked by advances in unified communication.

"The phone is going to be the PC, and the PC is going to be the phone," Gates said.

He also said software plus services, what Microsoft calls the "Live Era," also would be critical to deliver data and services so a user's information could follow them around.

Eric Lai of Computerworld contributed to this report.