LOS ANGELES – Microsoft Wednesday laid out its road map for Windows Server, including versions for small and midsize businesses based on Windows Server 2008 as well as a target date to ship the first update to the forthcoming server OS.

Bill Laing, general manager of the Windows server division, reiterated that Windows Server 2008, formerly called Longhorn, and Windows Home Server would ship this year. In 2008, Microsoft will ship Centro, the code name for a server for SMBs; Cougar, the next version of Small Business Server; and the next version of Windows Storage Server. All of those servers will be based on Windows Server 2008.

In 2009, Windows Server 2008 R2 will be released in 64-bit only and the era of 32-bit Windows servers will be over.

The R2 version of the server is part of an interim release cycle Microsoft established in May 2004 that called for a major operating system upgrade every four years with a lesser “R2” release in between.

Based on that release cycle, the replacement for Windows Server 2008 would ship in 2011. Laing did not mention that next release.

Laing also ignored changes in the feature set for Windows Virtualization Server (WVS) that Microsoft made last week, although he did say virtualization is a core part of Windows Server 2008.

Last week, Microsoft axed from WVS the Live Migration feature, which lets users move workloads between virtualized servers without any downtime.

Critics of Microsoft’s current Virtual Server software often cite its lack of live migration capabilities as one reason it is not ready to support performance-sensitive or critical applications.

Laing said Microsoft would license virtualization based on running instances of servers and not installations. Instances are images and copies of the original software stored on a local or storage network.

He stressed that Windows Server 2008 is an important step in building a new future for server technology.

“I believe the future will be standard and widely available software running on industry standard hardware,” Laing said.

He stressed that Windows Server 2008 is built on a foundation of management, including server core technology; security such as BitLocker drive encryption and read-only domain controllers; and performance such as IPv6 capabilities.